diff --git a/app/views/webhooks/_form.html.erb b/app/views/webhooks/_form.html.erb
--- a/app/views/webhooks/_form.html.erb
+++ b/app/views/webhooks/_form.html.erb
@@ -37,6 +37,7 @@
 
   <div class="splitcontentright">
     <fieldset class="box" id="webhook_project_ids"><legend><%= toggle_checkboxes_link("#webhook_project_ids input[type=checkbox]") %><%= l(:label_project_plural) %></legend>
+      <p><%= check_all_links 'webhook_project_ids' %></p>
       <% project_ids = @webhook.project_ids.to_a %>
       <%= render_project_nested_lists(@webhook.setable_projects) do |p|
         content_tag('label', check_box_tag('webhook[project_ids][]', p.id, project_ids.include?(p.id), :id => nil) + ' ' + h(p))
diff --git a/test/functional/webhooks_controller_test.rb b/test/functional/webhooks_controller_test.rb
--- a/test/functional/webhooks_controller_test.rb
+++ b/test/functional/webhooks_controller_test.rb
@@ -75,6 +75,8 @@ class WebhooksControllerTest < Redmine::ControllerTest
   test "should get edit" do
     get :edit, params: { id: @hook.id }
     assert_response :success
+    assert_select '#webhook_project_ids p a', text: I18n.t(:button_check_all)
+    assert_select '#webhook_project_ids p a', text: I18n.t(:button_uncheck_all)
   end
 
   test "should update webhook" do