diff --git a/CHANGELOG.md b/CHANGELOG.md
index af1e707..96bf2a7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -43,6 +43,7 @@ This document outlines major changes between releases.
 - Support new system attributes (#64)
 - Changed values for `frostfs_s3_gw_state_health` metric (#91)
 - Support multiple tree service endpoints (#74)
+- Timeout errors has code 504 now (#103)
 
 ### Removed
 - Drop `tree.service` param (now endpoints from `peers` section are used) (#133)
diff --git a/api/errors/errors.go b/api/errors/errors.go
index 78f0026..1ce4d0d 100644
--- a/api/errors/errors.go
+++ b/api/errors/errors.go
@@ -175,6 +175,7 @@ const (
 	// Add new extended error codes here.
 	ErrInvalidObjectName
 	ErrOperationTimedOut
+	ErrGatewayTimeout
 	ErrOperationMaxedOut
 	ErrInvalidRequest
 	ErrInvalidStorageClass
@@ -1124,6 +1125,12 @@ var errorCodes = errorCodeMap{
 		Description:    "A timeout occurred while trying to lock a resource, please reduce your request rate",
 		HTTPStatusCode: http.StatusServiceUnavailable,
 	},
+	ErrGatewayTimeout: {
+		ErrCode:        ErrGatewayTimeout,
+		Code:           "GatewayTimeout",
+		Description:    "The server is acting as a gateway and cannot get a response in time",
+		HTTPStatusCode: http.StatusGatewayTimeout,
+	},
 	ErrOperationMaxedOut: {
 		ErrCode:        ErrOperationMaxedOut,
 		Code:           "SlowDown",
diff --git a/api/handler/util.go b/api/handler/util.go
index 40cc57d..1d329a9 100644
--- a/api/handler/util.go
+++ b/api/handler/util.go
@@ -52,6 +52,10 @@ func transformToS3Error(err error) error {
 		return errors.GetAPIError(errors.ErrAccessDenied)
 	}
 
+	if errorsStd.Is(err, layer.ErrGatewayTimeout) {
+		return errors.GetAPIError(errors.ErrGatewayTimeout)
+	}
+
 	return errors.GetAPIError(errors.ErrInternalError)
 }
 
diff --git a/api/layer/frostfs.go b/api/layer/frostfs.go
index d22279a..2ec3a38 100644
--- a/api/layer/frostfs.go
+++ b/api/layer/frostfs.go
@@ -128,8 +128,13 @@ type PrmObjectDelete struct {
 	Object oid.ID
 }
 
-// ErrAccessDenied is returned from FrostFS in case of access violation.
-var ErrAccessDenied = errors.New("access denied")
+var (
+	// ErrAccessDenied is returned from FrostFS in case of access violation.
+	ErrAccessDenied = errors.New("access denied")
+
+	// ErrGatewayTimeout is returned from FrostFS in case of timeout, deadline exceeded etc.
+	ErrGatewayTimeout = errors.New("gateway timeout")
+)
 
 // FrostFS represents virtual connection to FrostFS network.
 type FrostFS interface {
diff --git a/internal/frostfs/errors/errors.go b/internal/frostfs/errors/errors.go
new file mode 100644
index 0000000..04574eb
--- /dev/null
+++ b/internal/frostfs/errors/errors.go
@@ -0,0 +1,42 @@
+package errors
+
+import (
+	"context"
+	"errors"
+	"strings"
+
+	apistatus "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client/status"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+func UnwrapErr(err error) error {
+	unwrappedErr := errors.Unwrap(err)
+	for unwrappedErr != nil {
+		err = unwrappedErr
+		unwrappedErr = errors.Unwrap(err)
+	}
+
+	return err
+}
+
+func IsErrObjectAccessDenied(err error) (string, bool) {
+	err = UnwrapErr(err)
+	switch err := err.(type) {
+	default:
+		return "", false
+	case apistatus.ObjectAccessDenied:
+		return err.Reason(), true
+	case *apistatus.ObjectAccessDenied:
+		return err.Reason(), true
+	}
+}
+
+func IsTimeoutError(err error) bool {
+	if strings.Contains(err.Error(), "timeout") ||
+		errors.Is(err, context.DeadlineExceeded) {
+		return true
+	}
+
+	return status.Code(UnwrapErr(err)) == codes.DeadlineExceeded
+}
diff --git a/internal/frostfs/frostfs.go b/internal/frostfs/frostfs.go
index 2274b8b..0770d40 100644
--- a/internal/frostfs/frostfs.go
+++ b/internal/frostfs/frostfs.go
@@ -14,7 +14,7 @@ import (
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/layer"
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/authmate"
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/creds/tokens"
-	apistatus "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client/status"
+	errorsFrost "git.frostfs.info/TrueCloudLab/frostfs-s3-gw/internal/frostfs/errors"
 	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container"
 	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/acl"
 	cid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/id"
@@ -61,7 +61,7 @@ func (x *FrostFS) TimeToEpoch(ctx context.Context, now, futureTime time.Time) (u
 
 	networkInfo, err := x.pool.NetworkInfo(ctx)
 	if err != nil {
-		return 0, 0, fmt.Errorf("get network info via client: %w", err)
+		return 0, 0, handleObjectError("get network info via client", err)
 	}
 
 	durEpoch := networkInfo.EpochDuration()
@@ -94,7 +94,7 @@ func (x *FrostFS) Container(ctx context.Context, idCnr cid.ID) (*container.Conta
 
 	res, err := x.pool.GetContainer(ctx, prm)
 	if err != nil {
-		return nil, fmt.Errorf("read container via connection pool: %w", err)
+		return nil, handleObjectError("read container via connection pool", err)
 	}
 
 	return &res, nil
@@ -136,7 +136,7 @@ func (x *FrostFS) CreateContainer(ctx context.Context, prm layer.PrmContainerCre
 
 	err := pool.SyncContainerWithNetwork(ctx, &cnr, x.pool)
 	if err != nil {
-		return cid.ID{}, fmt.Errorf("sync container with the network state: %w", err)
+		return cid.ID{}, handleObjectError("sync container with the network state", err)
 	}
 
 	var prmPut pool.PrmContainerPut
@@ -149,11 +149,7 @@ func (x *FrostFS) CreateContainer(ctx context.Context, prm layer.PrmContainerCre
 
 	// send request to save the container
 	idCnr, err := x.pool.PutContainer(ctx, prmPut)
-	if err != nil {
-		return cid.ID{}, fmt.Errorf("save container via connection pool: %w", err)
-	}
-
-	return idCnr, nil
+	return idCnr, handleObjectError("save container via connection pool", err)
 }
 
 // UserContainers implements frostfs.FrostFS interface method.
@@ -162,11 +158,7 @@ func (x *FrostFS) UserContainers(ctx context.Context, id user.ID) ([]cid.ID, err
 	prm.SetOwnerID(id)
 
 	r, err := x.pool.ListContainers(ctx, prm)
-	if err != nil {
-		return nil, fmt.Errorf("list user containers via connection pool: %w", err)
-	}
-
-	return r, nil
+	return r, handleObjectError("list user containers via connection pool", err)
 }
 
 // SetContainerEACL implements frostfs.FrostFS interface method.
@@ -180,11 +172,7 @@ func (x *FrostFS) SetContainerEACL(ctx context.Context, table eacl.Table, sessio
 	}
 
 	err := x.pool.SetEACL(ctx, prm)
-	if err != nil {
-		return fmt.Errorf("save eACL via connection pool: %w", err)
-	}
-
-	return err
+	return handleObjectError("save eACL via connection pool", err)
 }
 
 // ContainerEACL implements frostfs.FrostFS interface method.
@@ -194,7 +182,7 @@ func (x *FrostFS) ContainerEACL(ctx context.Context, id cid.ID) (*eacl.Table, er
 
 	res, err := x.pool.GetEACL(ctx, prm)
 	if err != nil {
-		return nil, fmt.Errorf("read eACL via connection pool: %w", err)
+		return nil, handleObjectError("read eACL via connection pool", err)
 	}
 
 	return &res, nil
@@ -211,11 +199,7 @@ func (x *FrostFS) DeleteContainer(ctx context.Context, id cid.ID, token *session
 	}
 
 	err := x.pool.DeleteContainer(ctx, prm)
-	if err != nil {
-		return fmt.Errorf("delete container via connection pool: %w", err)
-	}
-
-	return nil
+	return handleObjectError("delete container via connection pool", err)
 }
 
 // CreateObject implements frostfs.FrostFS interface method.
@@ -278,15 +262,7 @@ func (x *FrostFS) CreateObject(ctx context.Context, prm layer.PrmObjectCreate) (
 	}
 
 	idObj, err := x.pool.PutObject(ctx, prmPut)
-	if err != nil {
-		reason, ok := isErrAccessDenied(err)
-		if ok {
-			return oid.ID{}, fmt.Errorf("%w: %s", layer.ErrAccessDenied, reason)
-		}
-		return oid.ID{}, fmt.Errorf("save object via connection pool: %w", err)
-	}
-
-	return idObj, nil
+	return idObj, handleObjectError("save object via connection pool", err)
 }
 
 // wraps io.ReadCloser and transforms Read errors related to access violation
@@ -297,13 +273,7 @@ type payloadReader struct {
 
 func (x payloadReader) Read(p []byte) (int, error) {
 	n, err := x.ReadCloser.Read(p)
-	if err != nil {
-		if reason, ok := isErrAccessDenied(err); ok {
-			return n, fmt.Errorf("%w: %s", layer.ErrAccessDenied, reason)
-		}
-	}
-
-	return n, err
+	return n, handleObjectError("read payload", err)
 }
 
 // ReadObject implements frostfs.FrostFS interface method.
@@ -325,18 +295,14 @@ func (x *FrostFS) ReadObject(ctx context.Context, prm layer.PrmObjectRead) (*lay
 		if prm.WithPayload {
 			res, err := x.pool.GetObject(ctx, prmGet)
 			if err != nil {
-				if reason, ok := isErrAccessDenied(err); ok {
-					return nil, fmt.Errorf("%w: %s", layer.ErrAccessDenied, reason)
-				}
-
-				return nil, fmt.Errorf("init full object reading via connection pool: %w", err)
+				return nil, handleObjectError("init full object reading via connection pool", err)
 			}
 
 			defer res.Payload.Close()
 
 			payload, err := io.ReadAll(res.Payload)
 			if err != nil {
-				return nil, fmt.Errorf("read full object payload: %w", err)
+				return nil, handleObjectError("read full object payload", err)
 			}
 
 			res.Header.SetPayload(payload)
@@ -357,11 +323,7 @@ func (x *FrostFS) ReadObject(ctx context.Context, prm layer.PrmObjectRead) (*lay
 
 		hdr, err := x.pool.HeadObject(ctx, prmHead)
 		if err != nil {
-			if reason, ok := isErrAccessDenied(err); ok {
-				return nil, fmt.Errorf("%w: %s", layer.ErrAccessDenied, reason)
-			}
-
-			return nil, fmt.Errorf("read object header via connection pool: %w", err)
+			return nil, handleObjectError("read object header via connection pool", err)
 		}
 
 		return &layer.ObjectPart{
@@ -370,11 +332,7 @@ func (x *FrostFS) ReadObject(ctx context.Context, prm layer.PrmObjectRead) (*lay
 	} else if prm.PayloadRange[0]+prm.PayloadRange[1] == 0 {
 		res, err := x.pool.GetObject(ctx, prmGet)
 		if err != nil {
-			if reason, ok := isErrAccessDenied(err); ok {
-				return nil, fmt.Errorf("%w: %s", layer.ErrAccessDenied, reason)
-			}
-
-			return nil, fmt.Errorf("init full payload range reading via connection pool: %w", err)
+			return nil, handleObjectError("init full payload range reading via connection pool", err)
 		}
 
 		return &layer.ObjectPart{
@@ -395,11 +353,7 @@ func (x *FrostFS) ReadObject(ctx context.Context, prm layer.PrmObjectRead) (*lay
 
 	res, err := x.pool.ObjectRange(ctx, prmRange)
 	if err != nil {
-		if reason, ok := isErrAccessDenied(err); ok {
-			return nil, fmt.Errorf("%w: %s", layer.ErrAccessDenied, reason)
-		}
-
-		return nil, fmt.Errorf("init payload range reading via connection pool: %w", err)
+		return nil, handleObjectError("init payload range reading via connection pool", err)
 	}
 
 	return &layer.ObjectPart{
@@ -423,32 +377,7 @@ func (x *FrostFS) DeleteObject(ctx context.Context, prm layer.PrmObjectDelete) e
 	}
 
 	err := x.pool.DeleteObject(ctx, prmDelete)
-	if err != nil {
-		if reason, ok := isErrAccessDenied(err); ok {
-			return fmt.Errorf("%w: %s", layer.ErrAccessDenied, reason)
-		}
-
-		return fmt.Errorf("mark object removal via connection pool: %w", err)
-	}
-
-	return nil
-}
-
-func isErrAccessDenied(err error) (string, bool) {
-	unwrappedErr := errors.Unwrap(err)
-	for unwrappedErr != nil {
-		err = unwrappedErr
-		unwrappedErr = errors.Unwrap(err)
-	}
-
-	switch err := err.(type) {
-	default:
-		return "", false
-	case apistatus.ObjectAccessDenied:
-		return err.Reason(), true
-	case *apistatus.ObjectAccessDenied:
-		return err.Reason(), true
-	}
+	return handleObjectError("mark object removal via connection pool", err)
 }
 
 // ResolverFrostFS represents virtual connection to the FrostFS network.
@@ -466,7 +395,7 @@ func NewResolverFrostFS(p *pool.Pool) *ResolverFrostFS {
 func (x *ResolverFrostFS) SystemDNS(ctx context.Context) (string, error) {
 	networkInfo, err := x.pool.NetworkInfo(ctx)
 	if err != nil {
-		return "", fmt.Errorf("read network info via client: %w", err)
+		return "", handleObjectError("read network info via client", err)
 	}
 
 	domain := networkInfo.RawNetworkParameter("SystemDNS")
@@ -477,6 +406,22 @@ func (x *ResolverFrostFS) SystemDNS(ctx context.Context) (string, error) {
 	return string(domain), nil
 }
 
+func handleObjectError(msg string, err error) error {
+	if err == nil {
+		return nil
+	}
+
+	if reason, ok := errorsFrost.IsErrObjectAccessDenied(err); ok {
+		return fmt.Errorf("%s: %w: %s", msg, layer.ErrAccessDenied, reason)
+	}
+
+	if errorsFrost.IsTimeoutError(err) {
+		return fmt.Errorf("%s: %w: %s", msg, layer.ErrGatewayTimeout, err.Error())
+	}
+
+	return fmt.Errorf("%s: %w", msg, err)
+}
+
 // AuthmateFrostFS is a mediator which implements authmate.FrostFS through pool.Pool.
 type AuthmateFrostFS struct {
 	frostFS *FrostFS
diff --git a/internal/frostfs/frostfs_test.go b/internal/frostfs/frostfs_test.go
index e14dddc..134ff3c 100644
--- a/internal/frostfs/frostfs_test.go
+++ b/internal/frostfs/frostfs_test.go
@@ -1,12 +1,18 @@
 package frostfs
 
 import (
+	"context"
+	"errors"
 	"fmt"
 	"testing"
+	"time"
 
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/layer"
+	errorsFrost "git.frostfs.info/TrueCloudLab/frostfs-s3-gw/internal/frostfs/errors"
 	apistatus "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client/status"
 	"github.com/stretchr/testify/require"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
 )
 
 func TestErrorChecking(t *testing.T) {
@@ -16,10 +22,29 @@ func TestErrorChecking(t *testing.T) {
 
 	var wrappedError error
 
-	if fetchedReason, ok := isErrAccessDenied(err); ok {
+	if fetchedReason, ok := errorsFrost.IsErrObjectAccessDenied(err); ok {
 		wrappedError = fmt.Errorf("%w: %s", layer.ErrAccessDenied, fetchedReason)
 	}
 
 	require.ErrorIs(t, wrappedError, layer.ErrAccessDenied)
 	require.Contains(t, wrappedError.Error(), reason)
 }
+
+func TestErrorTimeoutChecking(t *testing.T) {
+	t.Run("simple timeout", func(t *testing.T) {
+		require.True(t, errorsFrost.IsTimeoutError(errors.New("timeout")))
+	})
+
+	t.Run("deadline exceeded", func(t *testing.T) {
+		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Millisecond)
+		defer cancel()
+		time.Sleep(50 * time.Millisecond)
+
+		require.True(t, errorsFrost.IsTimeoutError(ctx.Err()))
+	})
+
+	t.Run("grpc deadline exceeded", func(t *testing.T) {
+		err := fmt.Errorf("wrap grpc error: %w", status.Error(codes.DeadlineExceeded, "error"))
+		require.True(t, errorsFrost.IsTimeoutError(err))
+	})
+}
diff --git a/internal/frostfs/services/pool_wrapper.go b/internal/frostfs/services/pool_wrapper.go
index 03b21c9..4aa8f24 100644
--- a/internal/frostfs/services/pool_wrapper.go
+++ b/internal/frostfs/services/pool_wrapper.go
@@ -9,6 +9,7 @@ import (
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api"
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/data"
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/creds/accessbox"
+	errorsFrost "git.frostfs.info/TrueCloudLab/frostfs-s3-gw/internal/frostfs/errors"
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/pkg/service/tree"
 	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/bearer"
 	treepool "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/pool/tree"
@@ -188,6 +189,9 @@ func handleError(err error) error {
 	if errors.Is(err, treepool.ErrNodeAccessDenied) {
 		return fmt.Errorf("%w: %s", tree.ErrNodeAccessDenied, err.Error())
 	}
+	if errorsFrost.IsTimeoutError(err) {
+		return fmt.Errorf("%w: %s", tree.ErrGatewayTimeout, err.Error())
+	}
 
 	return err
 }
diff --git a/pkg/service/tree/tree.go b/pkg/service/tree/tree.go
index 87de268..21e2af3 100644
--- a/pkg/service/tree/tree.go
+++ b/pkg/service/tree/tree.go
@@ -62,6 +62,9 @@ var (
 
 	// ErrNodeAccessDenied is returned from ServiceClient service in case of access denied error.
 	ErrNodeAccessDenied = layer.ErrNodeAccessDenied
+
+	// ErrGatewayTimeout is returned from ServiceClient service in case of timeout error.
+	ErrGatewayTimeout = layer.ErrGatewayTimeout
 )
 
 const (