diff --git a/app/controllers/explore/projects_controller.rb b/app/controllers/explore/projects_controller.rb
index 577bd04d656fd14dac84d395939af48ec673e399..b3a1b510db9c76fd3bc49c0bae7809435845eb45 100644
--- a/app/controllers/explore/projects_controller.rb
+++ b/app/controllers/explore/projects_controller.rb
@@ -10,6 +10,7 @@ class Explore::ProjectsController < Explore::ApplicationController
 
   MIN_SEARCH_LENGTH = 3
   PAGE_LIMIT = 50
+  RSS_ENTRIES_LIMIT = 20
 
   before_action :set_non_archived_param
   before_action :set_sorting
@@ -83,6 +84,14 @@ def topic
 
     params[:topic] = @topic.name
     @projects = load_projects
+
+    respond_to do |format|
+      format.html
+      format.atom do
+        @projects = @projects.projects_order_id_desc.limit(RSS_ENTRIES_LIMIT)
+        render layout: 'xml'
+      end
+    end
   end
 
   private
diff --git a/app/views/explore/projects/_project.atom.builder b/app/views/explore/projects/_project.atom.builder
new file mode 100644
index 0000000000000000000000000000000000000000..f0500901a73f74ff5aa1d9cae5dbdff9c84ad6fb
--- /dev/null
+++ b/app/views/explore/projects/_project.atom.builder
@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+xml.entry do
+  xml.title   project.name
+  xml.link    href: project_url(project), rel: "alternate", type: "text/html"
+  xml.id      project_url(project)
+  xml.updated project.created_at
+
+  if project.description.present?
+    xml.summary(type: "xhtml") do |summary|
+      summary << project.description
+    end
+  end
+end
diff --git a/app/views/explore/projects/topic.atom.builder b/app/views/explore/projects/topic.atom.builder
new file mode 100644
index 0000000000000000000000000000000000000000..4712d415daa00bffac4b87abc4d0f474081cc3b4
--- /dev/null
+++ b/app/views/explore/projects/topic.atom.builder
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+xml.title   @topic.name
+xml.link    href: topic_explore_projects_url(@topic.name, rss_url_options), rel: "self", type: "application/atom+xml"
+xml.link    href: topic_explore_projects_url(@topic.name), rel: "alternate", type: "text/html"
+xml.id      topic_explore_projects_url(@topic.id)
+xml.updated @projects[0].updated_at.xmlschema if @projects[0]
+
+xml << render(@projects) if @projects.any?
diff --git a/app/views/explore/projects/topic.html.haml b/app/views/explore/projects/topic.html.haml
index b26abefcb0e62338c6ae11b1440db28b283af9c1..bba0c1b9ca0c532d7b0785772eeb11b82fb20b9b 100644
--- a/app/views/explore/projects/topic.html.haml
+++ b/app/views/explore/projects/topic.html.haml
@@ -22,9 +22,11 @@
 %div{ class: container_class }
   .gl-py-5.gl-border-gray-100.gl-border-b-solid.gl-border-b-1
     %h3.gl-m-0= _('Projects with this topic')
-  .top-area.gl-pt-2.gl-pb-2
+  .top-area.gl-pt-2.gl-pb-2.gl-justify-content-space-between
     .nav-controls
       = render 'shared/projects/search_form'
       = render 'filter'
+    = link_to topic_explore_projects_path(@topic.name, rss_url_options), title: s_("Topics|Subscribe to the new projects feed"), class: 'btn gl-button btn-default btn-icon d-none d-sm-inline-flex has-tooltip' do
+      = sprite_icon('rss', css_class: 'gl-icon')
 
   = render 'projects', projects: @projects
diff --git a/config/routes/explore.rb b/config/routes/explore.rb
index 6ddf4d2313861cb9d272014b41f232b48329d12e..6777571bb6830a90a5c428680fb33828d91ad3e3 100644
--- a/config/routes/explore.rb
+++ b/config/routes/explore.rb
@@ -6,7 +6,7 @@
       get :trending
       get :starred
       get :topics
-      get 'topics/:topic_name', action: :topic, as: :topic, constraints: { topic_name: /.+/ }
+      get 'topics/:topic_name', action: :topic, as: :topic, constraints: { format: /(html|atom)/, topic_name: /.+?/ }
     end
   end
 
diff --git a/doc/user/project/working_with_projects.md b/doc/user/project/working_with_projects.md
index 5bd7c12ed313a6ba66d9579e843a4614a68fbb47..ea937ed9244874f069280eac7fe33433b24c50b1 100644
--- a/doc/user/project/working_with_projects.md
+++ b/doc/user/project/working_with_projects.md
@@ -55,6 +55,10 @@ To explore project topics:
 
 The **Explore topics** page shows a list of topics, sorted by the number of associated projects.
 
+If you want to know when new projects are added to the topic, you can use
+its RSS feed for that, which is the RSS icon on the right of the filter
+bar.
+
 You can assign topics to a project on the [Project Settings page](settings/index.md#assign-topics-to-a-project).
 
 If you're an instance administrator, you can administer all project topics from the
diff --git a/locale/gitlab.pot b/locale/gitlab.pot
index ee98ce52a0c9ce1d7cc9c17d5ced3a7f52efc8cf..943112f4e0d7bae14d44424eedb8ce884fd1694f 100644
--- a/locale/gitlab.pot
+++ b/locale/gitlab.pot
@@ -48233,6 +48233,9 @@ msgstr ""
 msgid "Topics could not be merged!"
 msgstr ""
 
+msgid "Topics|Subscribe to the new projects feed"
+msgstr ""
+
 msgid "Total"
 msgstr ""
 
diff --git a/spec/controllers/explore/projects_controller_spec.rb b/spec/controllers/explore/projects_controller_spec.rb
index e73e115b77ded172e37033d5fbaaab738e22211e..68ae1ca218bf41d2a0096497fc72917ac00bfa53 100644
--- a/spec/controllers/explore/projects_controller_spec.rb
+++ b/spec/controllers/explore/projects_controller_spec.rb
@@ -122,6 +122,59 @@
         end
       end
     end
+
+    describe 'GET #topic.atom' do
+      context 'when topic does not exist' do
+        it 'renders a 404 error' do
+          get :topic, format: :atom, params: { topic_name: 'topic1' }
+
+          expect(response).to have_gitlab_http_status(:not_found)
+        end
+      end
+
+      context 'when topic exists' do
+        let(:topic) { create(:topic, name: 'topic1') }
+        let_it_be(:older_project) { create(:project, :public, updated_at: 1.day.ago) }
+        let_it_be(:newer_project) { create(:project, :public, updated_at: 2.days.ago) }
+
+        before do
+          create(:project_topic, project: older_project, topic: topic)
+          create(:project_topic, project: newer_project, topic: topic)
+        end
+
+        it 'renders the template' do
+          get :topic, format: :atom, params: { topic_name: 'topic1' }
+
+          expect(response).to have_gitlab_http_status(:ok)
+          expect(response).to render_template('topic', layout: :xml)
+        end
+
+        it 'sorts repos by descending creation date' do
+          get :topic, format: :atom, params: { topic_name: 'topic1' }
+
+          expect(assigns(:projects)).to match_array [newer_project, older_project]
+        end
+
+        it 'finds topic by case insensitive name' do
+          get :topic, format: :atom, params: { topic_name: 'TOPIC1' }
+
+          expect(response).to have_gitlab_http_status(:ok)
+          expect(response).to render_template('topic', layout: :xml)
+        end
+
+        describe 'when topic contains more than 20 projects' do
+          before do
+            create_list(:project, 22, :public, topics: [topic])
+          end
+
+          it 'does not assigns more than 20 projects' do
+            get :topic, format: :atom, params: { topic_name: 'topic1' }
+
+            expect(assigns(:projects).count).to be(20)
+          end
+        end
+      end
+    end
   end
 
   shared_examples "blocks high page numbers" do
diff --git a/spec/features/atom/topics_spec.rb b/spec/features/atom/topics_spec.rb
new file mode 100644
index 0000000000000000000000000000000000000000..078c5b55eeb36ee4abdc2ea08880ff90c482413d
--- /dev/null
+++ b/spec/features/atom/topics_spec.rb
@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe "Topic Feed", feature_category: :groups_and_projects do
+  let_it_be(:topic) { create(:topic, name: 'test-topic', title: 'Test topic') }
+  let_it_be(:empty_topic) { create(:topic, name: 'test-empty-topic', title: 'Test empty topic') }
+  let_it_be(:project1) { create(:project, :public, topic_list: topic.name) }
+  let_it_be(:project2) { create(:project, :public, topic_list: topic.name) }
+
+  context 'when topic does not exist' do
+    let(:path) { topic_explore_projects_path(topic_name: 'non-existing', format: 'atom') }
+
+    it 'renders 404' do
+      visit path
+
+      expect(status_code).to eq(404)
+    end
+  end
+
+  context 'when topic exists' do
+    before do
+      visit topic_explore_projects_path(topic_name: topic.name, format: 'atom')
+    end
+
+    it "renders topic atom feed" do
+      expect(body).to have_selector('feed title')
+    end
+
+    it "has project entries" do
+      expect(body).to have_content(project1.name)
+      expect(body).to have_content(project2.name)
+    end
+  end
+
+  context 'when topic is empty' do
+    before do
+      visit topic_explore_projects_path(topic_name: empty_topic.name, format: 'atom')
+    end
+
+    it "renders topic atom feed" do
+      expect(body).to have_selector('feed title')
+    end
+
+    it "has no project entry" do
+      expect(body).to have_no_selector('entry')
+    end
+  end
+end
diff --git a/spec/views/explore/projects/topic.html.haml_spec.rb b/spec/views/explore/projects/topic.html.haml_spec.rb
new file mode 100644
index 0000000000000000000000000000000000000000..1d2085b3be6d47595809ced1da20df79b76ab0bc
--- /dev/null
+++ b/spec/views/explore/projects/topic.html.haml_spec.rb
@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe 'explore/projects/topic.html.haml', feature_category: :groups_and_projects do
+  let(:topic) { build_stubbed(:topic, name: 'test-topic', title: 'Test topic') }
+  let(:project) { build_stubbed(:project, :public, topic_list: topic.name) }
+
+  before do
+    assign(:topic, topic)
+    assign(:projects, [project])
+
+    controller.params[:controller] = 'explore/projects'
+    controller.params[:action] = 'topic'
+
+    allow(view).to receive(:current_user).and_return(nil)
+
+    render
+  end
+
+  it 'renders atom feed button with matching path' do
+    expect(rendered).to have_link(href: topic_explore_projects_path(topic.name, format: 'atom'))
+  end
+end