diff --git a/changelogs/unreleased/26212-upload-user-avatar-trough-api.yml b/changelogs/unreleased/26212-upload-user-avatar-trough-api.yml
new file mode 100644
index 00000000000..667454ae95d
--- /dev/null
+++ b/changelogs/unreleased/26212-upload-user-avatar-trough-api.yml
@@ -0,0 +1,4 @@
+---
+title: Accept image for avatar in user API
+merge_request: 12143
+author: Ivan Chernov
diff --git a/doc/api/users.md b/doc/api/users.md
index 91ce4f6dac3..b1ebd7b0c47 100644
--- a/doc/api/users.md
+++ b/doc/api/users.md
@@ -251,6 +251,7 @@ Parameters:
 - `can_create_group` (optional) - User can create groups - true or false
 - `confirm` (optional)          - Require confirmation - true (default) or false
 - `external` (optional)         - Flags the user as external - true or false(default)
+- `avatar` (optional)           - Image file for user's avatar
 
 ## User modification
 
@@ -279,6 +280,7 @@ Parameters:
 - `admin` (optional)            - User is admin - true or false (default)
 - `can_create_group` (optional) - User can create groups - true or false
 - `external` (optional)         - Flags the user as external - true or false(default)
+- `avatar` (optional)           - Image file for user's avatar
 
 On password update, user will be forced to change it upon next login.
 Note, at the moment this method does only return a `404` error,
diff --git a/lib/api/users.rb b/lib/api/users.rb
index dda64715ee1..7257ecb5b67 100644
--- a/lib/api/users.rb
+++ b/lib/api/users.rb
@@ -29,6 +29,7 @@ module API
           optional :can_create_group, type: Boolean, desc: 'Flag indicating the user can create groups'
           optional :skip_confirmation, type: Boolean, default: false, desc: 'Flag indicating the account is confirmed'
           optional :external, type: Boolean, desc: 'Flag indicating the user is an external user'
+          optional :avatar, type: File, desc: 'Avatar image for user'
           all_or_none_of :extern_uid, :provider
         end
       end
diff --git a/spec/requests/api/users_spec.rb b/spec/requests/api/users_spec.rb
index 9dc4b6972a6..bc869ea1108 100644
--- a/spec/requests/api/users_spec.rb
+++ b/spec/requests/api/users_spec.rb
@@ -377,6 +377,16 @@ describe API::Users do
       expect(user.reload.organization).to eq('GitLab')
     end
 
+    it 'updates user with avatar' do
+      put api("/users/#{user.id}", admin), { avatar: fixture_file_upload(Rails.root + 'spec/fixtures/banana_sample.gif', 'image/gif') }
+
+      user.reload
+
+      expect(user.avatar).to be_present
+      expect(response).to have_http_status(200)
+      expect(json_response['avatar_url']).to include(user.avatar_path)
+    end
+
     it 'updates user with his own email' do
       put api("/users/#{user.id}", admin), email: user.email
       expect(response).to have_http_status(200)