diff --git a/api/handler/delete.go b/api/handler/delete.go
index f6cc994..1898949 100644
--- a/api/handler/delete.go
+++ b/api/handler/delete.go
@@ -8,7 +8,6 @@ import (
 	"github.com/nspcc-dev/neofs-s3-gw/api"
 	"github.com/nspcc-dev/neofs-s3-gw/api/layer"
 	"go.uber.org/zap"
-	"google.golang.org/grpc/status"
 )
 
 // DeleteObjectsRequest - xml carrying the object key names which needs to be deleted.
@@ -122,11 +121,6 @@ func (h *handler) DeleteMultipleObjectsHandler(w http.ResponseWriter, r *http.Re
 				code := "BadRequest"
 				desc := err.Error()
 
-				if st, ok := status.FromError(err.Err); ok && st != nil {
-					desc = st.Message()
-					code = st.Code().String()
-				}
-
 				response.Errors = append(response.Errors, DeleteError{
 					Code:    code,
 					Message: desc,
diff --git a/api/layer/layer.go b/api/layer/layer.go
index a3d348b..4718b16 100644
--- a/api/layer/layer.go
+++ b/api/layer/layer.go
@@ -19,8 +19,6 @@ import (
 	"github.com/nspcc-dev/neofs-s3-gw/creds/accessbox"
 	"github.com/nspcc-dev/neofs-sdk-go/pkg/pool"
 	"go.uber.org/zap"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/status"
 )
 
 type (
@@ -123,10 +121,6 @@ type (
 )
 
 var (
-	// ErrObjectExists is returned on attempts to create already existing object.
-	ErrObjectExists = errors.New("object exists")
-	// ErrObjectNotExists is returned on attempts to work with non-existing object.
-	ErrObjectNotExists = errors.New("object not exists")
 	// ErrBucketAlreadyExists is returned on attempts to create already existing bucket.
 	ErrBucketAlreadyExists = errors.New("bucket exists")
 	// ErrBucketNotFound is returned on attempts to get not existing bucket.
@@ -257,11 +251,7 @@ func (n *layer) checkObject(ctx context.Context, cid *cid.ID, filename string) e
 	var err error
 
 	if _, err = n.objectFindID(ctx, &findParams{cid: cid, val: filename}); err == nil {
-		return ErrObjectExists
-	} else if state, ok := status.FromError(err); !ok || state == nil {
-		return err
-	} else if state.Code() == codes.NotFound {
-		return ErrObjectNotExists
+		return new(api.ObjectAlreadyExists)
 	}
 
 	return err
diff --git a/api/layer/object.go b/api/layer/object.go
index 3116aad..fb31e22 100644
--- a/api/layer/object.go
+++ b/api/layer/object.go
@@ -81,7 +81,7 @@ func (n *layer) objectFindID(ctx context.Context, p *findParams) (*object.ID, er
 	if result, err := n.objectSearch(ctx, p); err != nil {
 		return nil, err
 	} else if ln := len(result); ln == 0 {
-		return nil, &api.ObjectNotFound{Bucket: p.cid.String(), Object: p.val}
+		return nil, api.GetAPIError(api.ErrNoSuchKey)
 	} else if ln == 1 {
 		return result[0], nil
 	}
@@ -123,12 +123,16 @@ func (n *layer) objectPut(ctx context.Context, p *PutObjectParams) (*ObjectInfo,
 		return nil, err
 	} else if bkt, err = n.GetBucketInfo(ctx, p.Bucket); err != nil {
 		return nil, err
-	} else if err = n.checkObject(ctx, bkt.CID, p.Object); err != nil && err != ErrObjectNotExists {
-		return nil, err
-	} else if err == ErrObjectExists {
-		return nil, &api.ObjectAlreadyExists{
-			Bucket: p.Bucket,
-			Object: p.Object,
+	} else if err = n.checkObject(ctx, bkt.CID, p.Object); err != nil {
+		var errExist *api.ObjectAlreadyExists
+		if ok := errors.As(err, &errExist); ok {
+			errExist.Bucket = p.Bucket
+			errExist.Object = p.Object
+			return nil, errExist
+		}
+
+		if !api.IsS3Error(err, api.ErrNoSuchKey) {
+			return nil, err
 		}
 	}