diff --git a/app/helpers/issuables_helper.rb b/app/helpers/issuables_helper.rb
index 8b97cf07fb9..ce2cabd7a3a 100644
--- a/app/helpers/issuables_helper.rb
+++ b/app/helpers/issuables_helper.rb
@@ -136,8 +136,19 @@ module IssuablesHelper
     html.html_safe
   end
 
+  def cached_assigned_issuables_count(assignee, issuable_type, state)
+    cache_key = hexdigest(['assigned_issuables_count', assignee.id, issuable_type, state].join('-'))
+    Rails.cache.fetch(cache_key, expires_in: 2.minutes) do
+      assigned_issuables_count(assignee, issuable_type, state)
+    end
+  end
+
   private
 
+  def assigned_issuables_count(assignee, issuable_type, state)
+    assignee.public_send("assigned_#{issuable_type}").public_send(state).count
+  end
+
   def sidebar_gutter_collapsed?
     cookies[:collapsed_gutter] == 'true'
   end
diff --git a/app/views/layouts/nav/_dashboard.html.haml b/app/views/layouts/nav/_dashboard.html.haml
index a0356feef95..2a6d9cda379 100644
--- a/app/views/layouts/nav/_dashboard.html.haml
+++ b/app/views/layouts/nav/_dashboard.html.haml
@@ -26,12 +26,12 @@
       = link_to assigned_issues_dashboard_path, title: 'Issues', class: 'dashboard-shortcuts-issues' do
         %span
           Issues
-          %span.count= number_with_delimiter(current_user.assigned_issues.opened.count)
+          %span.count= number_with_delimiter(cached_assigned_issuables_count(current_user, :issues, :opened))
     = nav_link(path: 'dashboard#merge_requests') do
       = link_to assigned_mrs_dashboard_path, title: 'Merge Requests', class: 'dashboard-shortcuts-merge_requests' do
         %span
           Merge Requests
-          %span.count= number_with_delimiter(current_user.assigned_merge_requests.opened.count)
+          %span.count= number_with_delimiter(cached_assigned_issuables_count(current_user, :merge_requests, :opened))
     = nav_link(controller: 'dashboard/snippets') do
       = link_to dashboard_snippets_path, title: 'Snippets' do
         %span
diff --git a/changelogs/unreleased/fix_navigation_bar_issuables_counters.yml b/changelogs/unreleased/fix_navigation_bar_issuables_counters.yml
new file mode 100644
index 00000000000..0f7f8155f91
--- /dev/null
+++ b/changelogs/unreleased/fix_navigation_bar_issuables_counters.yml
@@ -0,0 +1,4 @@
+---
+title: Navigation bar issuables counters reflects dashboard issuables counters
+merge_request: 7368
+author: Lucas Deschamps
diff --git a/spec/features/dashboard/issuables_counter_spec.rb b/spec/features/dashboard/issuables_counter_spec.rb
new file mode 100644
index 00000000000..41dcfe439c2
--- /dev/null
+++ b/spec/features/dashboard/issuables_counter_spec.rb
@@ -0,0 +1,44 @@
+require 'spec_helper'
+
+describe 'Navigation bar counter', feature: true, js: true, caching: true do
+  let(:user) { create(:user) }
+  let(:project) { create(:empty_project, namespace: user.namespace) }
+  let(:issue) { create(:issue, project: project) }
+  let(:merge_request) { create(:merge_request, source_project: project) }
+
+  before do
+    issue.update(assignee: user)
+    merge_request.update(assignee: user)
+    login_as(user)
+  end
+
+  it 'reflects dashboard issues count' do
+    visit issues_dashboard_path
+
+    expect_counters('issues', '1')
+
+    issue.update(assignee: nil)
+    visit issues_dashboard_path
+
+    expect_counters('issues', '1')
+  end
+
+  it 'reflects dashboard merge requests count' do
+    visit merge_requests_dashboard_path
+
+    expect_counters('merge_requests', '1')
+
+    merge_request.update(assignee: nil)
+    visit merge_requests_dashboard_path
+
+    expect_counters('merge_requests', '1')
+  end
+
+  def expect_counters(issuable_type, count)
+    dashboard_count = find('li.active span.badge')
+    nav_count = find(".dashboard-shortcuts-#{issuable_type} span.count")
+
+    expect(nav_count).to have_content(count)
+    expect(dashboard_count).to have_content(count)
+  end
+end