diff --git a/app/controllers/repositories_controller.rb b/app/controllers/repositories_controller.rb
index 269bc70a0..92a145c3a 100644
--- a/app/controllers/repositories_controller.rb
+++ b/app/controllers/repositories_controller.rb
@@ -35,6 +35,7 @@ class RepositoriesController < ApplicationController
   before_action :find_changeset, :only => [:revision, :add_related_issue, :remove_related_issue]
   before_action :authorize
   accept_rss_auth :revisions
+  accept_api_auth :add_related_issue, :remove_related_issue
 
   rescue_from Redmine::Scm::Adapters::CommandFailed, :with => :show_error_command_failed
 
@@ -227,8 +228,14 @@ class RepositoriesController < ApplicationController
       @issue = nil
     end
 
-    if @issue
-      @changeset.issues << @issue
+    respond_to do |format|
+      if @issue
+        @changeset.issues << @issue
+        format.api { render_api_ok }
+      else
+        format.api { render_api_errors "#{l(:label_issue)} #{l('activerecord.errors.messages.invalid')}" }
+      end
+      format.js
     end
   end
 
@@ -239,6 +246,10 @@ class RepositoriesController < ApplicationController
     if @issue
       @changeset.issues.delete(@issue)
     end
+    respond_to do |format|
+      format.api { render_api_ok }
+      format.js
+    end
   end
 
   def diff
diff --git a/test/integration/api_test/api_routing_test.rb b/test/integration/api_test/api_routing_test.rb
index 692389b2b..8af27179a 100644
--- a/test/integration/api_test/api_routing_test.rb
+++ b/test/integration/api_test/api_routing_test.rb
@@ -117,6 +117,11 @@ class Redmine::ApiTest::ApiRoutingTest < Redmine::ApiTest::Routing
     should_route 'GET /queries' => 'queries#index'
   end
 
+  def test_repositories
+    should_route 'POST /projects/1/repository/2/revisions/3/issues' => 'repositories#add_related_issue', :id => '1', :repository_id => '2', :rev => '3'
+    should_route 'DELETE /projects/1/repository/2/revisions/3/issues/4' => 'repositories#remove_related_issue', :id => '1', :repository_id => '2', :rev => '3', :issue_id => '4'
+  end
+
   def test_roles
     should_route 'GET /roles' => 'roles#index'
     should_route 'GET /roles/2' => 'roles#show', :id => '2'
diff --git a/test/integration/api_test/repositories_test.rb b/test/integration/api_test/repositories_test.rb
new file mode 100644
index 000000000..29ca13d29
--- /dev/null
+++ b/test/integration/api_test/repositories_test.rb
@@ -0,0 +1,107 @@
+# frozen_string_literal: true
+
+# Redmine - project management software
+# Copyright (C) 2006-2019  Jean-Philippe Lang
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+require File.expand_path('../../../test_helper', __FILE__)
+
+class Redmine::ApiTest::RepositoriesTest < Redmine::ApiTest::Base
+  fixtures :users,
+           :projects, :enabled_modules,
+           :members, :roles, :member_roles,
+           :issues,
+           :repositories, :changesets, :changes
+
+  test 'POST /projects/:id/repository/:repository_id/revisions/:rev/issues.xml should add related issue' do
+    changeset = Changeset.find(103)
+    assert_equal [], changeset.issue_ids
+    assert_difference 'Changeset.find(103).issues.size' do
+      post '/projects/1/repository/10/revisions/4/issues.xml', :headers => credentials('jsmith'), :params => {:issue_id => '2'}
+    end
+    assert_response :no_content
+    assert_equal [2], changeset.reload.issue_ids
+  end
+
+  test 'POST /projects/:id/repository/:repository_id/revisions/:rev/issues.json should add related issue' do
+    changeset = Changeset.find(103)
+    assert_equal [], changeset.issue_ids
+    assert_difference 'Changeset.find(103).issues.size' do
+      post '/projects/1/repository/10/revisions/4/issues.json', :headers => credentials('jsmith'), :params => {:issue_id => '2'}
+    end
+    assert_response :no_content
+    assert_equal [2], changeset.reload.issue_ids
+  end
+
+  test 'POST /projects/:id/repository/:repository_id/revisions/:rev/issues.xml should accept issue_id with sharp' do
+    changeset = Changeset.find(103)
+    assert_equal [], changeset.issue_ids
+    assert_difference 'Changeset.find(103).issues.size' do
+      post '/projects/1/repository/10/revisions/4/issues.xml', :headers => credentials('jsmith'), :params => {:issue_id => '#2'}
+    end
+    assert_response :no_content
+    assert_equal [2], changeset.reload.issue_ids
+  end
+
+  test 'POST /projects/:id/repository/:repository_id/revisions/:rev/issues.json should accept issue_id with sharp' do
+    changeset = Changeset.find(103)
+    assert_equal [], changeset.issue_ids
+    assert_difference 'Changeset.find(103).issues.size' do
+      post '/projects/1/repository/10/revisions/4/issues.json', :headers => credentials('jsmith'), :params => {:issue_id => '#2'}
+    end
+    assert_response :no_content
+    assert_equal [2], changeset.reload.issue_ids
+  end
+
+  test 'POST /projects/:id/repository/:repository_id/revisions/:rev/issues.xml with invalid issue_id' do
+    assert_no_difference 'Changeset.find(103).issues.size' do
+      post '/projects/1/repository/10/revisions/4/issues.xml', :headers => credentials('jsmith'), :params => {:issue_id => '9999'}
+    end
+    assert_response :unprocessable_entity
+    assert_select 'errors error', :text => 'Issue is invalid'
+  end
+
+  test 'POST /projects/:id/repository/:repository_id/revisions/:rev/issues.json with invalid issue_id' do
+    assert_no_difference 'Changeset.find(103).issues.size' do
+      post '/projects/1/repository/10/revisions/4/issues.json', :headers => credentials('jsmith'), :params => {:issue_id => '9999'}
+    end
+    assert_response :unprocessable_entity
+    json = ActiveSupport::JSON.decode(response.body)
+    assert json['errors'].include?('Issue is invalid')
+  end
+
+  test 'DELETE /projects/:id/repository/:repository_id/revisions/:rev/issues/:issue_id.xml should remove related issue' do
+    changeset = Changeset.find(103)
+    changeset.issues << Issue.find(1)
+    changeset.issues << Issue.find(2)
+    assert_difference 'Changeset.find(103).issues.size', -1 do
+      delete '/projects/1/repository/10/revisions/4/issues/2.xml', :headers => credentials('jsmith')
+    end
+    assert_response :no_content
+    assert_equal [1], changeset.reload.issue_ids
+  end
+
+  test 'DELETE /projects/:id/repository/:repository_id/revisions/:rev/issues/:issue_id.json should remove related issue' do
+    changeset = Changeset.find(103)
+    changeset.issues << Issue.find(1)
+    changeset.issues << Issue.find(2)
+    assert_difference 'Changeset.find(103).issues.size', -1 do
+      delete '/projects/1/repository/10/revisions/4/issues/2.json', :headers => credentials('jsmith')
+    end
+    assert_response :no_content
+    assert_equal [1], changeset.reload.issue_ids
+  end
+end