diff --git a/core/modules/comment/comment.module b/core/modules/comment/comment.module
index bb203bf..b9d84e4 100644
--- a/core/modules/comment/comment.module
+++ b/core/modules/comment/comment.module
@@ -661,11 +661,17 @@ function template_preprocess_comment(&$variables) {
   else {
     $uri = $comment->permalink();
     $attributes = $uri->getOption('attributes') ?: [];
-    $attributes += ['class' => ['permalink'], 'rel' => 'bookmark'];
+    $attributes += ['class' => ['permalink']];
+    if (CommentType::load($comment->bundle())->getNofollow()) {
+      $attributes += ['rel' => 'bookmark nofollow'];
+    }
+    else {
+      $attributes += ['rel' => 'bookmark'];
+    }
     $uri->setOption('attributes', $attributes);
     $variables['title'] = \Drupal::l($comment->getSubject(), $uri);
 
-    $variables['permalink'] = \Drupal::l(t('Permalink'), $comment->permalink());
+    $variables['permalink'] = \Drupal::l(t('Permalink'), $uri);
   }
 
   $variables['submitted'] = t('Submitted by @username on @datetime', ['@username' => $variables['author'], '@datetime' => $variables['created']]);
@@ -690,7 +696,13 @@ function template_preprocess_comment(&$variables) {
     }
     $permalink_uri_parent = $comment_parent->permalink();
     $attributes = $permalink_uri_parent->getOption('attributes') ?: [];
-    $attributes += ['class' => ['permalink'], 'rel' => 'bookmark'];
+    $attributes += ['class' => ['permalink']];
+    if (CommentType::load($comment_parent->bundle())->getNofollow()) {
+      $attributes += ['rel' => 'bookmark nofollow'];
+    }
+    else {
+      $attributes += ['rel' => 'bookmark'];
+    }
     $permalink_uri_parent->setOption('attributes', $attributes);
     $variables['parent_title'] = \Drupal::l($comment_parent->getSubject(), $permalink_uri_parent);
     $variables['parent_permalink'] = \Drupal::l(t('Parent permalink'), $permalink_uri_parent);
diff --git a/core/modules/comment/config/schema/comment.schema.yml b/core/modules/comment/config/schema/comment.schema.yml
index 045e9ad..a344f10 100644
--- a/core/modules/comment/config/schema/comment.schema.yml
+++ b/core/modules/comment/config/schema/comment.schema.yml
@@ -58,6 +58,9 @@ comment.type.*:
     description:
       type: text
       label: 'Description'
+    nofollow:
+      type: boolean
+      label: 'Rel nofollow'
 
 field.storage_settings.comment:
   type: mapping
diff --git a/core/modules/comment/src/CommentTypeForm.php b/core/modules/comment/src/CommentTypeForm.php
index 0ac5b44..64033b7 100644
--- a/core/modules/comment/src/CommentTypeForm.php
+++ b/core/modules/comment/src/CommentTypeForm.php
@@ -122,6 +122,13 @@ public function form(array $form, FormStateInterface $form_state) {
       ];
     }
 
+    $form['nofollow'] = [
+      '#type' => 'checkbox',
+      '#title' => t('Nofollow'),
+      '#default_value' => $comment_type->getNofollow(),
+      '#description' => t('Add nofollow to rel attribute of comment type.'),
+    ];
+
     if ($this->moduleHandler->moduleExists('content_translation')) {
       $form['language'] = [
         '#type' => 'details',
diff --git a/core/modules/comment/src/CommentTypeInterface.php b/core/modules/comment/src/CommentTypeInterface.php
index acde96c..4653576 100644
--- a/core/modules/comment/src/CommentTypeInterface.php
+++ b/core/modules/comment/src/CommentTypeInterface.php
@@ -35,4 +35,11 @@ public function setDescription($description);
    */
   public function getTargetEntityTypeId();
 
+  /**
+   * Gets the setting of rel's nofollow for this comment type.
+   *
+   * @return bool
+   *   TRUE if the comment type has the rel set to nofollow, FALSE otherwise.
+   */
+  public function getNofollow();
 }
diff --git a/core/modules/comment/src/Entity/CommentType.php b/core/modules/comment/src/Entity/CommentType.php
index a773c58..62009db 100644
--- a/core/modules/comment/src/Entity/CommentType.php
+++ b/core/modules/comment/src/Entity/CommentType.php
@@ -44,6 +44,7 @@
  *     "label",
  *     "target_entity_type_id",
  *     "description",
+ *     "nofollow",
  *   }
  * )
  */
@@ -78,6 +79,13 @@ class CommentType extends ConfigEntityBundleBase implements CommentTypeInterface
   protected $target_entity_type_id;
 
   /**
+   * Whether the comment type has rel set to nofollow.
+   *
+   * @var bool
+   */
+  protected $nofollow = TRUE;
+
+  /**
    * {@inheritdoc}
    */
   public function getDescription() {
@@ -99,4 +107,11 @@ public function getTargetEntityTypeId() {
     return $this->target_entity_type_id;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getNofollow() {
+    return $this->nofollow;
+  }
+
 }
diff --git a/core/modules/comment/src/Tests/CommentTestBase.php b/core/modules/comment/src/Tests/CommentTestBase.php
index 3b923ff..7210065 100644
--- a/core/modules/comment/src/Tests/CommentTestBase.php
+++ b/core/modules/comment/src/Tests/CommentTestBase.php
@@ -401,6 +401,7 @@ protected function createCommentType($label) {
       'label' => $label,
       'description' => '',
       'target_entity_type_id' => 'node',
+      'nofollow' => TRUE,
     ]);
     $bundle->save();
     return $bundle;
diff --git a/core/modules/comment/src/Tests/CommentTestTrait.php b/core/modules/comment/src/Tests/CommentTestTrait.php
index 038a3df..739aace 100644
--- a/core/modules/comment/src/Tests/CommentTestTrait.php
+++ b/core/modules/comment/src/Tests/CommentTestTrait.php
@@ -47,6 +47,7 @@ public function addDefaultCommentField($entity_type, $bundle, $field_name = 'com
         'id' => $comment_type_id,
         'label' => Unicode::ucfirst($comment_type_id),
         'target_entity_type_id' => $entity_type,
+        'nofollow' => TRUE,
         'description' => 'Default comment field',
       ])->save();
     }
diff --git a/core/modules/comment/tests/src/Functional/CommentFieldsTest.php b/core/modules/comment/tests/src/Functional/CommentFieldsTest.php
index 2df9973..dc5aa2f 100644
--- a/core/modules/comment/tests/src/Functional/CommentFieldsTest.php
+++ b/core/modules/comment/tests/src/Functional/CommentFieldsTest.php
@@ -168,6 +168,7 @@ public function testCommentFieldCreate() {
       'label' => 'user_comment_type',
       'description' => '',
       'target_entity_type_id' => 'user',
+      'nofollow' => TRUE,
     ]);
     $bundle->save();
 
diff --git a/core/modules/comment/tests/src/Functional/CommentNonNodeTest.php b/core/modules/comment/tests/src/Functional/CommentNonNodeTest.php
index 5889d69..19dc593 100644
--- a/core/modules/comment/tests/src/Functional/CommentNonNodeTest.php
+++ b/core/modules/comment/tests/src/Functional/CommentNonNodeTest.php
@@ -56,6 +56,7 @@ protected function setUp() {
       'label' => 'Comment settings',
       'description' => 'Comment settings',
       'target_entity_type_id' => 'entity_test',
+      'nofollow' => TRUE,
     ])->save();
     // Create comment field on entity_test bundle.
     $this->addDefaultCommentField('entity_test', 'entity_test');
@@ -411,6 +412,7 @@ public function testCommentFunctionality() {
       'label' => 'Foobar',
       'description' => '',
       'target_entity_type_id' => 'entity_test',
+      'nofollow' => TRUE,
     ]);
     $bundle->save();
 
diff --git a/core/modules/comment/tests/src/Functional/CommentTestBase.php b/core/modules/comment/tests/src/Functional/CommentTestBase.php
index 7cadcbf..e00126c 100644
--- a/core/modules/comment/tests/src/Functional/CommentTestBase.php
+++ b/core/modules/comment/tests/src/Functional/CommentTestBase.php
@@ -395,6 +395,7 @@ protected function createCommentType($label) {
       'label' => $label,
       'description' => '',
       'target_entity_type_id' => 'node',
+      'nofollow' => TRUE,
     ]);
     $bundle->save();
     return $bundle;
diff --git a/core/modules/comment/tests/src/Kernel/CommentBundlesTest.php b/core/modules/comment/tests/src/Kernel/CommentBundlesTest.php
index d907233..de1c84a 100644
--- a/core/modules/comment/tests/src/Kernel/CommentBundlesTest.php
+++ b/core/modules/comment/tests/src/Kernel/CommentBundlesTest.php
@@ -51,6 +51,7 @@ protected function setUp() {
         'id' => 'comment_on_' . $id,
         'label' => 'Comment on ' . $label,
         'target_entity_type_id' => $id,
+        'nofollow' => TRUE,
       ])->save();
     }
   }
diff --git a/core/modules/comment/tests/src/Kernel/CommentFieldAccessTest.php b/core/modules/comment/tests/src/Kernel/CommentFieldAccessTest.php
index 1e0fd72..0d7c377 100644
--- a/core/modules/comment/tests/src/Kernel/CommentFieldAccessTest.php
+++ b/core/modules/comment/tests/src/Kernel/CommentFieldAccessTest.php
@@ -99,6 +99,7 @@ public function testAccessToAdministrativeFields() {
       'label' => 'Default comments',
       'description' => 'Default comment field',
       'target_entity_type_id' => 'entity_test',
+      'nofollow' => TRUE,
     ]);
     $comment_type->save();
 
diff --git a/core/modules/comment/tests/src/Kernel/CommentStringIdEntitiesTest.php b/core/modules/comment/tests/src/Kernel/CommentStringIdEntitiesTest.php
index adbe1b0..2f6519c 100644
--- a/core/modules/comment/tests/src/Kernel/CommentStringIdEntitiesTest.php
+++ b/core/modules/comment/tests/src/Kernel/CommentStringIdEntitiesTest.php
@@ -45,6 +45,7 @@ public function testCommentFieldNonStringId() {
         'label' => 'foo',
         'description' => '',
         'target_entity_type_id' => 'entity_test_string_id',
+        'nofollow' => TRUE,
       ]);
       $bundle->save();
       $field_storage = FieldStorageConfig::create([
diff --git a/core/modules/comment/tests/src/Kernel/Migrate/MigrateCommentStubTest.php b/core/modules/comment/tests/src/Kernel/Migrate/MigrateCommentStubTest.php
index 0b256ea..cf3744f 100644
--- a/core/modules/comment/tests/src/Kernel/Migrate/MigrateCommentStubTest.php
+++ b/core/modules/comment/tests/src/Kernel/Migrate/MigrateCommentStubTest.php
@@ -48,6 +48,7 @@ protected function setUp() {
       'id' => 'testcommenttype',
       'label' => 'Test comment type',
       'target_entity_type_id' => 'node',
+      'nofollow' => TRUE,
     ])->save();
   }
 
diff --git a/core/modules/comment/tests/src/Kernel/Views/CommentAdminViewTest.php b/core/modules/comment/tests/src/Kernel/Views/CommentAdminViewTest.php
index 86e8949..f9c553d 100644
--- a/core/modules/comment/tests/src/Kernel/Views/CommentAdminViewTest.php
+++ b/core/modules/comment/tests/src/Kernel/Views/CommentAdminViewTest.php
@@ -87,6 +87,7 @@ protected function setUp($import_test_views = TRUE) {
       'label' => 'Default comments',
       'target_entity_type_id' => 'entity_test',
       'description' => 'Default comment field',
+      'nofollow' => TRUE,
     ])->save();
     // Create a commented entity.
     $entity = EntityTest::create();
diff --git a/core/modules/rest/tests/src/Functional/EntityResource/CommentType/CommentTypeResourceTestBase.php b/core/modules/rest/tests/src/Functional/EntityResource/CommentType/CommentTypeResourceTestBase.php
index 9d88211..968998a 100644
--- a/core/modules/rest/tests/src/Functional/EntityResource/CommentType/CommentTypeResourceTestBase.php
+++ b/core/modules/rest/tests/src/Functional/EntityResource/CommentType/CommentTypeResourceTestBase.php
@@ -44,6 +44,7 @@ protected function createEntity() {
       'label' => 'Camelids',
       'description' => 'Camelids are large, strictly herbivorous animals with slender necks and long legs.',
       'target_entity_type_id' => 'node',
+      'nofollow' => TRUE,
     ]);
 
     $camelids->save();
@@ -63,6 +64,7 @@ protected function getExpectedNormalizedEntity() {
       'langcode' => 'en',
       'status' => TRUE,
       'target_entity_type_id' => 'node',
+      'nofollow' => TRUE,
       'uuid' => $this->entity->uuid(),
     ];
   }