diff --git a/lib/classes/hook/manager.php b/lib/classes/hook/manager.php
index 4bc1140b442..73a05df13e1 100644
--- a/lib/classes/hook/manager.php
+++ b/lib/classes/hook/manager.php
@@ -89,30 +89,6 @@ final class manager implements
         return $instance;
     }
 
-    /**
-     * Reset all hook caches. This is intended to be called only
-     * from the admin/hooks.php page after callback override is changed.
-     *
-     * @return void
-     * @codeCoverageIgnore
-     */
-    public function reset_caches(): void {
-        if (PHPUNIT_TEST && $this === self::$instance) {
-            debugging('\core\hook\manager::get_instance()->reset_caches() is not supposed to be called in PHPUnit tests',
-                DEBUG_DEVELOPER);
-            return;
-        }
-
-        // WARNING: This will not work when callback overrides are changed
-        // and multiple web nodes with local cache stores are present - in that
-        // case admins must purge all caches when tweaking callback overrides.
-        $cache = \cache::make('core', 'hookcallbacks');
-        $cache->delete('callbacks');
-        $cache->delete('deprecations');
-
-        $this->init_standard_callbacks();
-    }
-
     /**
      * Returns list of callbacks for given hook name.
      *
diff --git a/lib/tests/hook/manager_test.php b/lib/tests/hook/manager_test.php
index 70f702e761e..e6f2674cd2a 100644
--- a/lib/tests/hook/manager_test.php
+++ b/lib/tests/hook/manager_test.php
@@ -56,24 +56,6 @@ class manager_test extends \advanced_testcase {
         $this->assertSame(['test_plugin\\hook\\hook'], $testmanager->get_hooks_with_callbacks());
     }
 
-    /**
-     * Test reset of test instance.
-     *
-     * NOTE: normal hook manger instance cannot be reset in PHPUnit test
-     * because it may be used to control the test environment itself.
-     *
-     * @covers ::reset_caches
-     * @covers ::init_standard_callbacks
-     */
-    public function test_reset_caches() {
-        $testmanager = manager::phpunit_get_instance([]);
-        $this->assertSame([], $testmanager->get_hooks_with_callbacks());
-
-        $testmanager->reset_caches();
-        $manager = manager::get_instance();
-        $this->assertSame($manager->get_hooks_with_callbacks(), $testmanager->get_hooks_with_callbacks());
-    }
-
     /**
      * Test loading and parsing of callbacks from files.
      *