diff --git a/app/controllers/projects/settings/repository_controller.rb b/app/controllers/projects/settings/repository_controller.rb
index ac3004d069f..bc2ce15286f 100644
--- a/app/controllers/projects/settings/repository_controller.rb
+++ b/app/controllers/projects/settings/repository_controller.rb
@@ -99,7 +99,7 @@ module Projects
       end
 
       def deploy_token_params
-        params.require(:deploy_token).permit(:name, :expires_at, :read_repository, :read_registry)
+        params.require(:deploy_token).permit(:name, :expires_at, :read_repository, :read_registry, :username)
       end
     end
   end
diff --git a/app/models/deploy_token.rb b/app/models/deploy_token.rb
index b0e570f52ba..33f0be91632 100644
--- a/app/models/deploy_token.rb
+++ b/app/models/deploy_token.rb
@@ -16,6 +16,14 @@ class DeployToken < ApplicationRecord
   has_many :projects, through: :project_deploy_tokens
 
   validate :ensure_at_least_one_scope
+  validates :username,
+    length: { maximum: 255 },
+    allow_nil: true,
+    format: {
+      with: /\A[a-zA-Z0-9\.\+_-]+\z/,
+      message: "can contain only letters, digits, '_', '-', '+', and '.'"
+    }
+
   before_save :ensure_token
 
   accepts_nested_attributes_for :project_deploy_tokens
@@ -39,7 +47,7 @@ class DeployToken < ApplicationRecord
   end
 
   def username
-    "gitlab+deploy-token-#{id}"
+    super || default_username
   end
 
   def has_access_to?(requested_project)
@@ -75,4 +83,8 @@ class DeployToken < ApplicationRecord
   def ensure_at_least_one_scope
     errors.add(:base, "Scopes can't be blank") unless read_repository || read_registry
   end
+
+  def default_username
+    "gitlab+deploy-token-#{id}" if persisted?
+  end
 end
diff --git a/app/services/deploy_tokens/create_service.rb b/app/services/deploy_tokens/create_service.rb
index dc0122002e9..327a1dbf408 100644
--- a/app/services/deploy_tokens/create_service.rb
+++ b/app/services/deploy_tokens/create_service.rb
@@ -3,7 +3,9 @@
 module DeployTokens
   class CreateService < BaseService
     def execute
-      @project.deploy_tokens.create(params)
+      @project.deploy_tokens.create(params) do |deploy_token|
+        deploy_token.username = params[:username].presence
+      end
     end
   end
 end
diff --git a/app/views/projects/deploy_tokens/_form.html.haml b/app/views/projects/deploy_tokens/_form.html.haml
index 5412fcbc9d8..f846dbd3763 100644
--- a/app/views/projects/deploy_tokens/_form.html.haml
+++ b/app/views/projects/deploy_tokens/_form.html.haml
@@ -12,6 +12,11 @@
     = f.label :expires_at, class: 'label-bold'
     = f.text_field :expires_at, class: 'datepicker form-control qa-deploy-token-expires-at', value: f.object.expires_at
 
+  .form-group
+    = f.label :username, class: 'label-bold'
+    = f.text_field :username, class: 'form-control qa-deploy-token-username'
+    .text-secondary= s_('DeployTokens|Default format is "gitlab+deploy-token-{n}". Enter custom username if you want to change it.')
+
   .form-group
     = f.label :scopes, class: 'label-bold'
     %fieldset.form-group.form-check
diff --git a/changelogs/unreleased/50228-deploy-tokens-custom-username.yml b/changelogs/unreleased/50228-deploy-tokens-custom-username.yml
new file mode 100644
index 00000000000..fdafa7b1113
--- /dev/null
+++ b/changelogs/unreleased/50228-deploy-tokens-custom-username.yml
@@ -0,0 +1,5 @@
+---
+title: Allow custom username for deploy tokens
+merge_request: 29639
+author:
+type: added
diff --git a/db/migrate/20190613044655_add_username_to_deploy_tokens.rb b/db/migrate/20190613044655_add_username_to_deploy_tokens.rb
new file mode 100644
index 00000000000..793553afe35
--- /dev/null
+++ b/db/migrate/20190613044655_add_username_to_deploy_tokens.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+class AddUsernameToDeployTokens < ActiveRecord::Migration[5.1]
+  DOWNTIME = false
+
+  def change
+    add_column :deploy_tokens, :username, :string
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 7948f919c57..143f6c7127e 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -1047,6 +1047,7 @@ ActiveRecord::Schema.define(version: 20190628145246) do
     t.datetime_with_timezone "created_at", null: false
     t.string "name", null: false
     t.string "token", null: false
+    t.string "username"
     t.index ["token", "expires_at", "id"], name: "index_deploy_tokens_on_token_and_expires_at_and_id", where: "(revoked IS FALSE)", using: :btree
     t.index ["token"], name: "index_deploy_tokens_on_token", unique: true, using: :btree
   end
diff --git a/locale/gitlab.pot b/locale/gitlab.pot
index 60d4e199a9f..72324674bbc 100644
--- a/locale/gitlab.pot
+++ b/locale/gitlab.pot
@@ -3557,6 +3557,9 @@ msgstr ""
 msgid "DeployTokens|Created"
 msgstr ""
 
+msgid "DeployTokens|Default format is \"gitlab+deploy-token-{n}\". Enter custom username if you want to change it."
+msgstr ""
+
 msgid "DeployTokens|Deploy Tokens"
 msgstr ""
 
diff --git a/spec/controllers/projects/settings/repository_controller_spec.rb b/spec/controllers/projects/settings/repository_controller_spec.rb
index b34053fc993..7f67f67e775 100644
--- a/spec/controllers/projects/settings/repository_controller_spec.rb
+++ b/spec/controllers/projects/settings/repository_controller_spec.rb
@@ -32,4 +32,24 @@ describe Projects::Settings::RepositoryController do
       expect(RepositoryCleanupWorker).to have_received(:perform_async).once
     end
   end
+
+  describe 'POST create_deploy_token' do
+    let(:deploy_token_params) do
+      {
+        name: 'deployer_token',
+        expires_at: 1.month.from_now.to_date.to_s,
+        username: 'deployer',
+        read_repository: '1'
+      }
+    end
+
+    subject(:create_deploy_token) { post :create_deploy_token, params: { namespace_id: project.namespace, project_id: project, deploy_token: deploy_token_params } }
+
+    it 'creates deploy token' do
+      expect { create_deploy_token }.to change { DeployToken.active.count }.by(1)
+
+      expect(response).to have_gitlab_http_status(200)
+      expect(response).to render_template(:show)
+    end
+  end
 end
diff --git a/spec/features/projects/settings/repository_settings_spec.rb b/spec/features/projects/settings/repository_settings_spec.rb
index 8c7bc192c50..1edfee705c8 100644
--- a/spec/features/projects/settings/repository_settings_spec.rb
+++ b/spec/features/projects/settings/repository_settings_spec.rb
@@ -112,11 +112,17 @@ describe 'Projects > Settings > Repository settings' do
       it 'add a new deploy token' do
         fill_in 'deploy_token_name', with: 'new_deploy_key'
         fill_in 'deploy_token_expires_at', with: (Date.today + 1.month).to_s
+        fill_in 'deploy_token_username', with: 'deployer'
         check 'deploy_token_read_repository'
         check 'deploy_token_read_registry'
         click_button 'Create deploy token'
 
         expect(page).to have_content('Your new project deploy token has been created')
+
+        within('.created-deploy-token-container') do
+          expect(page).to have_selector("input[name='deploy-token-user'][value='deployer']")
+          expect(page).to have_selector("input[name='deploy-token'][readonly='readonly']")
+        end
       end
     end
 
diff --git a/spec/lib/gitlab/auth_spec.rb b/spec/lib/gitlab/auth_spec.rb
index 3b5ca7c950c..d9c73cff01e 100644
--- a/spec/lib/gitlab/auth_spec.rb
+++ b/spec/lib/gitlab/auth_spec.rb
@@ -309,6 +309,15 @@ describe Gitlab::Auth do
             .to eq(auth_success)
         end
 
+        it 'succeeds when custom login and token are valid' do
+          deploy_token = create(:deploy_token, username: 'deployer', read_registry: false, projects: [project])
+          auth_success = Gitlab::Auth::Result.new(deploy_token, project, :deploy_token, [:download_code])
+
+          expect(gl_auth).to receive(:rate_limit!).with('ip', success: true, login: 'deployer')
+          expect(gl_auth.find_for_git_client('deployer', deploy_token.token, project: project, ip: 'ip'))
+            .to eq(auth_success)
+        end
+
         it 'fails when login is not valid' do
           expect(gl_auth).to receive(:rate_limit!).with('ip', success: false, login: 'random_login')
           expect(gl_auth.find_for_git_client('random_login', deploy_token.token, project: project, ip: 'ip'))
diff --git a/spec/models/deploy_token_spec.rb b/spec/models/deploy_token_spec.rb
index 2fe82eaa778..8d951ab6f0f 100644
--- a/spec/models/deploy_token_spec.rb
+++ b/spec/models/deploy_token_spec.rb
@@ -8,6 +8,15 @@ describe DeployToken do
   it { is_expected.to have_many :project_deploy_tokens }
   it { is_expected.to have_many(:projects).through(:project_deploy_tokens) }
 
+  describe 'validations' do
+    let(:username_format_message) { "can contain only letters, digits, '_', '-', '+', and '.'" }
+
+    it { is_expected.to validate_length_of(:username).is_at_most(255) }
+    it { is_expected.to allow_value('GitLab+deploy_token-3.14').for(:username) }
+    it { is_expected.not_to allow_value('<script>').for(:username).with_message(username_format_message) }
+    it { is_expected.not_to allow_value('').for(:username).with_message(username_format_message) }
+  end
+
   describe '#ensure_token' do
     it 'ensures a token' do
       deploy_token.token = nil
@@ -87,8 +96,30 @@ describe DeployToken do
   end
 
   describe '#username' do
-    it 'returns a harcoded username' do
-      expect(deploy_token.username).to eq("gitlab+deploy-token-#{deploy_token.id}")
+    context 'persisted records' do
+      it 'returns a default username if none is set' do
+        expect(deploy_token.username).to eq("gitlab+deploy-token-#{deploy_token.id}")
+      end
+
+      it 'returns the username provided if one is set' do
+        deploy_token = create(:deploy_token, username: 'deployer')
+
+        expect(deploy_token.username).to eq('deployer')
+      end
+    end
+
+    context 'new records' do
+      it 'returns nil if no username is set' do
+        deploy_token = build(:deploy_token)
+
+        expect(deploy_token.username).to be_nil
+      end
+
+      it 'returns the username provided if one is set' do
+        deploy_token = build(:deploy_token, username: 'deployer')
+
+        expect(deploy_token.username).to eq('deployer')
+      end
     end
   end
 
diff --git a/spec/services/deploy_tokens/create_service_spec.rb b/spec/services/deploy_tokens/create_service_spec.rb
index 886ffd4593d..fbb66fe4cb7 100644
--- a/spec/services/deploy_tokens/create_service_spec.rb
+++ b/spec/services/deploy_tokens/create_service_spec.rb
@@ -32,6 +32,22 @@ describe DeployTokens::CreateService do
       end
     end
 
+    context 'when username is empty string' do
+      let(:deploy_token_params) { attributes_for(:deploy_token, username: '') }
+
+      it 'converts it to nil' do
+        expect(subject.read_attribute(:username)).to be_nil
+      end
+    end
+
+    context 'when username is provided' do
+      let(:deploy_token_params) { attributes_for(:deploy_token, username: 'deployer') }
+
+      it 'keeps the provided username' do
+        expect(subject.read_attribute(:username)).to eq('deployer')
+      end
+    end
+
     context 'when the deploy token is invalid' do
       let(:deploy_token_params) { attributes_for(:deploy_token, read_repository: false, read_registry: false) }