diff --git a/object/types.proto b/object/types.proto
index cb6fe91..8169645 100644
--- a/object/types.proto
+++ b/object/types.proto
@@ -124,6 +124,8 @@ message Header {
   //   File name to be associated with the object on saving
   // * Timestamp \
   //   User-defined local time of object creation in Unix Timestamp format
+  // * Content-Type \
+  //   MIME Content Type of object's payload
   //
   // For detailed description of each well-known attribute please see the
   // corresponding section in NeoFS Technical specification.
diff --git a/proto-docs/object.md b/proto-docs/object.md
index 355f7a4..ce3fb52 100644
--- a/proto-docs/object.md
+++ b/proto-docs/object.md
@@ -699,6 +699,8 @@ And some well-known attributes used by applications only:
   File name to be associated with the object on saving
 * Timestamp \
   User-defined local time of object creation in Unix Timestamp format
+* Content-Type \
+  MIME Content Type of object's payload
 
 For detailed description of each well-known attribute please see the
 corresponding section in NeoFS Technical specification.