diff -u b/core/modules/taxonomy/src/Entity/Term.php b/core/modules/taxonomy/src/Entity/Term.php
--- b/core/modules/taxonomy/src/Entity/Term.php
+++ b/core/modules/taxonomy/src/Entity/Term.php
@@ -65,9 +65,10 @@
   public static function postDelete(EntityStorageInterface $storage, array $entities) {
     parent::postDelete($storage, $entities);
 
+    $tids = array_keys($entities);
     // See if any of the term's children are about to be become orphans.
     $orphans = array();
-    foreach (array_keys($entities) as $tid) {
+    foreach ($tids as $tid) {
       if ($children = taxonomy_term_load_children($tid)) {
         foreach ($children as $child) {
           // If the term has multiple parents, we don't delete it.
@@ -81,8 +82,7 @@
 
     // Delete term hierarchy information after looking up orphans but before
     // deleting them so that their children/parent information is consistent.
-    $storage->deleteTermHierarchy(array_keys($entities));
-    $storage->deleteTermHierarchyByParent(array_keys($entities));
+    $storage->deleteTermHierarchy($tids);
 
     if (!empty($orphans)) {
       entity_delete_multiple('taxonomy_term', $orphans);
@@ -98,7 +98,6 @@
     // Only change the parents if a value is set, keep the existing values if
     // not.
     if (isset($this->parent->target_id)) {
-      $storage->deleteTermHierarchy(array($this->id()));
       $storage->updateTermHierarchy($this);
     }
   }
diff -u b/core/modules/taxonomy/src/TermStorage.php b/core/modules/taxonomy/src/TermStorage.php
--- b/core/modules/taxonomy/src/TermStorage.php
+++ b/core/modules/taxonomy/src/TermStorage.php
@@ -101,16 +101,10 @@
    */
   public function deleteTermHierarchy($tids) {
     $this->database->delete('taxonomy_term_hierarchy')
-      ->condition('tid', $tids, 'IN')
-      ->execute();
-  }
-
-  /**
-   *{@inheritdoc}
-   */
-  public function deleteTermHierarchyByParent($pids) {
-    $this->database->delete('taxonomy_term_hierarchy')
-      ->condition('parent', $pids, 'IN')
+      ->condition(db_or()
+        ->condition('tid', $tids, 'IN')
+        ->condition('parent', $tids, 'IN')
+      )
       ->execute();
   }
 
@@ -118,6 +112,10 @@
    * {@inheritdoc}
    */
   public function updateTermHierarchy(EntityInterface $term) {
+    // Remove the term from taxonomy_term_hierarchy before repopulating.
+    $this->database->delete('taxonomy_term_hierarchy')
+      ->condition('tid', $term->id())
+      ->execute();
     $query = $this->database->insert('taxonomy_term_hierarchy')
       ->fields(array('tid', 'parent'));
 
diff -u b/core/modules/taxonomy/src/TermStorageInterface.php b/core/modules/taxonomy/src/TermStorageInterface.php
--- b/core/modules/taxonomy/src/TermStorageInterface.php
+++ b/core/modules/taxonomy/src/TermStorageInterface.php
@@ -24,14 +24,6 @@
   public function deleteTermHierarchy($tids);
 
   /**
-   * Removes reference to terms from term_hierarchy parent.
-   *
-   * @param array $pids
-   *  Array of parent terms that need to be removed from hierarchy.
-   */
-  public function deleteTermHierarchyByParent($pids);
-
-  /**
    * Updates terms hierarchy information with the hierarchy trail of it.
    *
    * @param \Drupal\Core\Entity\EntityInterface $term