diff --git a/app/controllers/projects/notes_controller.rb b/app/controllers/projects/notes_controller.rb
index 2154b6ed2eb77e47b38da99b80e620eb8b6f7f0c..7b08b79d236ef1a4061a3adf5409ba049ebb4fe5 100644
--- a/app/controllers/projects/notes_controller.rb
+++ b/app/controllers/projects/notes_controller.rb
@@ -30,8 +30,10 @@ class Projects::NotesController < Projects::ApplicationController
   end
 
   def update
-    note.update_attributes(note_params)
-    note.reset_events_cache
+    if note.editable?
+      note.update_attributes(note_params)
+      note.reset_events_cache
+    end
 
     respond_to do |format|
       format.json { render_note_json(note) }
@@ -40,8 +42,10 @@ class Projects::NotesController < Projects::ApplicationController
   end
 
   def destroy
-    note.destroy
-    note.reset_events_cache
+    if note.editable?
+      note.destroy
+      note.reset_events_cache
+    end
 
     respond_to do |format|
       format.js { render nothing: true }
diff --git a/app/models/note.rb b/app/models/note.rb
index 01f72b95c4808e5c047430f88af32d2d4d14ea33..0fa1a7ab615615fc7e4d7c1b4017ec52ea005b3d 100644
--- a/app/models/note.rb
+++ b/app/models/note.rb
@@ -337,4 +337,8 @@ class Note < ActiveRecord::Base
   def set_references
     notice_added_references(project, author)
   end
+
+  def editable?
+    !system
+  end
 end
diff --git a/app/views/projects/notes/_note.html.haml b/app/views/projects/notes/_note.html.haml
index 90fc554e987d09a4a568e58ecae1847b2cd3f929..394fa88e04591be2784aea3ca3e0f1230409a6ef 100644
--- a/app/views/projects/notes/_note.html.haml
+++ b/app/views/projects/notes/_note.html.haml
@@ -9,7 +9,7 @@
             %i.icon-link
             Link here
           &nbsp;
-          - if(note.author_id == current_user.try(:id)) || can?(current_user, :admin_note, @project)
+          - if can?(current_user, :admin_note, note) && note.editable?
             = link_to "#", title: "Edit comment", class: "js-note-edit" do
               %i.icon-edit
               Edit