diff --git a/core/includes/database.inc b/core/includes/database.inc
index 1f7dc8b7d12..7e2fe41ef10 100644
--- a/core/includes/database.inc
+++ b/core/includes/database.inc
@@ -721,6 +721,10 @@ function db_field_exists($table, $field) {
  * @see \Drupal\Core\Database\Schema::findTables()
  */
 function db_find_tables($table_expression) {
+  @trigger_error(
+    'db_find_tables() is deprecated in Drupal 8.0.x and will be removed before Drupal 9.0.0. Use $injected_database->schema()->findTables($table_expression) instead. See https://www.drupal.org/node/2993033',
+    E_USER_DEPRECATED
+  );
   return Database::getConnection()->schema()->findTables($table_expression);
 }
 
diff --git a/core/modules/simpletest/simpletest.module b/core/modules/simpletest/simpletest.module
index 1b603ab7364..0a9c8e524a3 100644
--- a/core/modules/simpletest/simpletest.module
+++ b/core/modules/simpletest/simpletest.module
@@ -670,7 +670,7 @@ function simpletest_clean_environment() {
  */
 function simpletest_clean_database() {
   $schema = Database::getConnection()->schema();
-  $tables = db_find_tables('test%');
+  $tables = $schema->findTables('test%');
   $count = 0;
   foreach ($tables as $table) {
     // Only drop tables which begin wih 'test' followed by digits, for example,
diff --git a/core/modules/system/src/Tests/Module/ModuleTestBase.php b/core/modules/system/src/Tests/Module/ModuleTestBase.php
index 257bb879cf7..30f89a34318 100644
--- a/core/modules/system/src/Tests/Module/ModuleTestBase.php
+++ b/core/modules/system/src/Tests/Module/ModuleTestBase.php
@@ -42,7 +42,8 @@ abstract class ModuleTestBase extends WebTestBase {
    *   specified base table. Defaults to TRUE.
    */
   public function assertTableCount($base_table, $count = TRUE) {
-    $tables = db_find_tables(Database::getConnection()->prefixTables('{' . $base_table . '}') . '%');
+    $connection = Database::getConnection();
+    $tables = $connection->schema()->findTables($connection->prefixTables('{' . $base_table . '}') . '%');
 
     if ($count) {
       return $this->assertTrue($tables, format_string('Tables matching "@base_table" found.', ['@base_table' => $base_table]));
diff --git a/core/modules/system/tests/src/Functional/Module/ModuleTestBase.php b/core/modules/system/tests/src/Functional/Module/ModuleTestBase.php
index 6cc726326dc..e48770d4995 100644
--- a/core/modules/system/tests/src/Functional/Module/ModuleTestBase.php
+++ b/core/modules/system/tests/src/Functional/Module/ModuleTestBase.php
@@ -39,7 +39,8 @@ abstract class ModuleTestBase extends BrowserTestBase {
    *   specified base table. Defaults to TRUE.
    */
   public function assertTableCount($base_table, $count = TRUE) {
-    $tables = db_find_tables(Database::getConnection()->prefixTables('{' . $base_table . '}') . '%');
+    $connection = Database::getConnection();
+    $tables = $connection->schema()->findTables($connection->prefixTables('{' . $base_table . '}') . '%');
 
     if ($count) {
       return $this->assertTrue($tables, format_string('Tables matching "@base_table" found.', ['@base_table' => $base_table]));
diff --git a/core/tests/Drupal/KernelTests/Core/Database/DatabaseLegacyTest.php b/core/tests/Drupal/KernelTests/Core/Database/DatabaseLegacyTest.php
index 3c950c9be75..1724f1475d7 100644
--- a/core/tests/Drupal/KernelTests/Core/Database/DatabaseLegacyTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Database/DatabaseLegacyTest.php
@@ -71,6 +71,19 @@ class DatabaseLegacyTest extends DatabaseTestBase {
     $this->assertTrue(db_table_exists('test'));
   }
 
+  /**
+   * Tests the db_find_tables() function.
+   *
+   * @expectedDeprecation db_find_tables() is deprecated in Drupal 8.0.x and will be removed before Drupal 9.0.0. Use $injected_database->schema()->findTables($table_expression) instead. See https://www.drupal.org/node/2993033
+   */
+  public function testDbFindTables() {
+    $expected = [
+      'test_people' => 'test_people',
+      'test_people_copy' => 'test_people_copy',
+    ];
+    $this->assertEquals($expected, db_find_tables('test_people%'));
+  }
+
   /**
    * Tests the db_set_active() function.
    *