diff --git a/app/models/namespace.rb b/app/models/namespace.rb
index dea34e812ca..8638c5a9c53 100644
--- a/app/models/namespace.rb
+++ b/app/models/namespace.rb
@@ -51,6 +51,7 @@ class Namespace < ApplicationRecord
   validate :nesting_level_allowed
 
   delegate :name, to: :owner, allow_nil: true, prefix: true
+  delegate :avatar_url, to: :owner, allow_nil: true
 
   after_commit :refresh_access_of_projects_invited_groups, on: :update, if: -> { previous_changes.key?('share_with_group_lock') }
 
@@ -149,6 +150,10 @@ class Namespace < ApplicationRecord
     type == 'Group' ? 'group' : 'user'
   end
 
+  def user?
+    kind == 'user'
+  end
+
   def find_fork_of(project)
     return unless project.fork_network
 
diff --git a/doc/api/projects.md b/doc/api/projects.md
index 0a950352ecf..951961e45ff 100644
--- a/doc/api/projects.md
+++ b/doc/api/projects.md
@@ -494,7 +494,9 @@ GET /projects/:id
     "name": "Diaspora",
     "path": "diaspora",
     "kind": "group",
-    "full_path": "diaspora"
+    "full_path": "diaspora",
+    "avatar_url": "http://localhost:3000/uploads/group/avatar/3/foo.jpg",
+    "web_url": "http://localhost:3000/groups/diaspora"
   },
   "import_status": "none",
   "import_error": null,
@@ -561,6 +563,8 @@ GET /projects/:id
 }
 ```
 
+**Note**: The `web_url` and `avatar_url` attributes on `namespace` were [introduced][ce-27427] in GitLab 11.11.
+
 If the project is a fork, and you provide a valid token to authenticate, the
 `forked_from_project` field will appear in the response.
 
@@ -1587,3 +1591,4 @@ GET /projects/:id/snapshot
 
 [eep]: https://about.gitlab.com/pricing/ "Available only in GitLab Premium"
 [ee-6137]: https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/6137
+[ce-27427]: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/27427
diff --git a/lib/api/entities.rb b/lib/api/entities.rb
index 4bdac278add..ee8480122c4 100644
--- a/lib/api/entities.rb
+++ b/lib/api/entities.rb
@@ -922,7 +922,15 @@ module API
     end
 
     class NamespaceBasic < Grape::Entity
-      expose :id, :name, :path, :kind, :full_path, :parent_id
+      expose :id, :name, :path, :kind, :full_path, :parent_id, :avatar_url
+
+      expose :web_url do |namespace|
+        if namespace.user?
+          Gitlab::Routing.url_helpers.user_url(namespace.owner)
+        else
+          namespace.web_url
+        end
+      end
     end
 
     class Namespace < NamespaceBasic
diff --git a/spec/models/namespace_spec.rb b/spec/models/namespace_spec.rb
index 387d1221c76..95a4b0f6d71 100644
--- a/spec/models/namespace_spec.rb
+++ b/spec/models/namespace_spec.rb
@@ -63,6 +63,11 @@ describe Namespace do
     end
   end
 
+  describe 'delegate' do
+    it { is_expected.to delegate_method(:name).to(:owner).with_prefix.with_arguments(allow_nil: true) }
+    it { is_expected.to delegate_method(:avatar_url).to(:owner).with_arguments(allow_nil: true) }
+  end
+
   describe "Respond to" do
     it { is_expected.to respond_to(:human_name) }
     it { is_expected.to respond_to(:to_param) }
@@ -801,4 +806,21 @@ describe Namespace do
       end
     end
   end
+
+  describe '#user?' do
+    subject { namespace.user? }
+
+    context 'when type is a user' do
+      let(:user) { create(:user) }
+      let(:namespace) { user.namespace }
+
+      it { is_expected.to be_truthy }
+    end
+
+    context 'when type is a group' do
+      let(:namespace) { create(:group) }
+
+      it { is_expected.to be_falsy }
+    end
+  end
 end
diff --git a/spec/requests/api/projects_spec.rb b/spec/requests/api/projects_spec.rb
index 352ea448c00..577f61ae8d0 100644
--- a/spec/requests/api/projects_spec.rb
+++ b/spec/requests/api/projects_spec.rb
@@ -1047,7 +1047,6 @@ describe API::Projects do
         expect(json_response['http_url_to_repo']).to be_present
         expect(json_response['web_url']).to be_present
         expect(json_response['owner']).to be_a Hash
-        expect(json_response['owner']).to be_a Hash
         expect(json_response['name']).to eq(project.name)
         expect(json_response['path']).to be_present
         expect(json_response['issues_enabled']).to be_present
@@ -1135,7 +1134,9 @@ describe API::Projects do
           'path' => user.namespace.path,
           'kind' => user.namespace.kind,
           'full_path' => user.namespace.full_path,
-          'parent_id' => nil
+          'parent_id' => nil,
+          'avatar_url' => user.avatar_url,
+          'web_url' => Gitlab::Routing.url_helpers.user_url(user)
         })
       end
 
@@ -1337,6 +1338,37 @@ describe API::Projects do
           end
         end
       end
+
+      context 'when project belongs to a group namespace' do
+        let(:group) { create(:group, :with_avatar) }
+        let(:project) { create(:project, namespace: group) }
+        let!(:project_member) { create(:project_member, :developer, user: user, project: project) }
+
+        it 'returns group web_url and avatar_url' do
+          get api("/projects/#{project.id}", user)
+
+          expect(response).to have_gitlab_http_status(200)
+
+          group_data = json_response['namespace']
+          expect(group_data['web_url']).to eq(group.web_url)
+          expect(group_data['avatar_url']).to eq(group.avatar_url)
+        end
+      end
+
+      context 'when project belongs to a user namespace' do
+        let(:user) { create(:user) }
+        let(:project) { create(:project, namespace: user.namespace) }
+
+        it 'returns user web_url and avatar_url' do
+          get api("/projects/#{project.id}", user)
+
+          expect(response).to have_gitlab_http_status(200)
+
+          user_data = json_response['namespace']
+          expect(user_data['web_url']).to eq("http://localhost/#{user.username}")
+          expect(user_data['avatar_url']).to eq(user.avatar_url)
+        end
+      end
     end
 
     context 'with external authorization' do