diff --git a/core/core.services.yml b/core/core.services.yml
index 6954b56..72fee69 100644
--- a/core/core.services.yml
+++ b/core/core.services.yml
@@ -291,7 +291,7 @@ services:
     arguments: ['@app.root', '%container.modules%', '@cache.bootstrap']
   module_installer:
     class: Drupal\Core\Extension\ModuleInstaller
-    arguments: ['@app.root', '@module_handler', '@kernel']
+    arguments: ['@app.root', '@module_handler', '@kernel', '@entity.manager', '@entity.query']
   theme_handler:
     class: Drupal\Core\Extension\ThemeHandler
     arguments: ['@app.root', '@config.factory', '@module_handler', '@state', '@info_parser', '@logger.channel.default', '@asset.css.collection_optimizer', '@config.installer', '@config.manager', '@router.builder_indicator']
diff --git a/core/lib/Drupal/Core/Extension/ModuleInstaller.php b/core/lib/Drupal/Core/Extension/ModuleInstaller.php
index f074ed3..e7955ef 100644
--- a/core/lib/Drupal/Core/Extension/ModuleInstaller.php
+++ b/core/lib/Drupal/Core/Extension/ModuleInstaller.php
@@ -10,6 +10,8 @@
 use Drupal\Component\Serialization\Yaml;
 use Drupal\Core\Cache\CacheBackendInterface;
 use Drupal\Core\DrupalKernelInterface;
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Entity\Query\QueryFactory;
 
 /**
  * Default implementation of the module installer.
@@ -41,6 +43,27 @@ class ModuleInstaller implements ModuleInstallerInterface {
   protected $root;
 
   /**
+   * The entity manager.
+   *
+   * @var \Drupal\Core\Entity\EntityManagerInterface
+   */
+  protected $entityManager;
+
+  /**
+   * The entity query factory.
+   *
+   * @var \Drupal\Core\Entity\Query\QueryFactory
+   */
+  protected $queryFactory;
+
+  /**
+   * Modules that can be uninstalled.
+   *
+   * @var array
+   */
+  protected $uninstallValidated;
+
+  /**
    * Constructs a new ModuleInstaller instance.
    *
    * @param string $root
@@ -49,14 +72,20 @@ class ModuleInstaller implements ModuleInstallerInterface {
    *   The module handler.
    * @param \Drupal\Core\DrupalKernelInterface $kernel
    *   The drupal kernel.
+   * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager.
+   * @param \Drupal\Core\Entity\Query\QueryFactory $entity_query
+   *   The entity query factory.
    *
    * @see \Drupal\Core\DrupalKernel
    * @see \Drupal\Core\CoreServiceProvider
    */
-  public function __construct($root, ModuleHandlerInterface $module_handler, DrupalKernelInterface $kernel) {
+  public function __construct($root, ModuleHandlerInterface $module_handler, DrupalKernelInterface $kernel, EntityManagerInterface $entity_manager, QueryFactory $entity_query) {
     $this->root = $root;
     $this->moduleHandler = $module_handler;
     $this->kernel = $kernel;
+    $this->entityManager = $entity_manager;
+    $this->entityQueryFactory = $entity_query;
   }
 
   /**
@@ -270,6 +299,7 @@ public function install(array $module_list, $enable_dependencies = TRUE) {
    * {@inheritdoc}
    */
   public function uninstall(array $module_list, $uninstall_dependents = TRUE) {
+    $module_list = $this->validateUninstall($module_list);
     // Get all module data so we can find dependencies and sort.
     $module_data = system_rebuild_module_data();
     $module_list = $module_list ? array_combine($module_list, $module_list) : array();
@@ -460,4 +490,47 @@ protected function updateKernel($module_filenames) {
     $this->moduleHandler = $container->get('module_handler');
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function validateUninstall(array $module_list) {
+    foreach ($module_list as $module) {
+      if (isset($this->uninstallValidated[$module])) {
+        continue;
+      }
+      if ($this->moduleHasContent($module)) {
+        unset($module_list[$module]);
+      }
+      else {
+        $this->uninstallValidated[] = $module;
+      }
+    }
+    return $module_list;
+  }
+
+  /**
+   * Determines if a module has existing content entities.
+   *
+   * @param string $module
+   *   A module name.
+   *
+   * @return bool
+   *   TRUE if there are content entities.
+   */
+  protected function moduleHasContent($module) {
+    $entities = $this->entityManager->getDefinitions();
+    foreach ($entities as $entity_type) {
+      if ($module == $entity_type->getProvider() && is_subclass_of($entity_type->getClass(), 'Drupal\Core\Entity\ContentEntityInterface')) {
+        $content = $this->queryFactory->get($entity_type->id())
+            ->accessCheck(FALSE)
+            ->range(0, 1)
+            ->execute();
+        if (!empty($content)) {
+          return TRUE;
+        }
+      }
+    }
+    return FALSE;
+  }
+
 }
diff --git a/core/lib/Drupal/Core/Extension/ModuleInstallerInterface.php b/core/lib/Drupal/Core/Extension/ModuleInstallerInterface.php
index 246af4b..b11bc3e 100644
--- a/core/lib/Drupal/Core/Extension/ModuleInstallerInterface.php
+++ b/core/lib/Drupal/Core/Extension/ModuleInstallerInterface.php
@@ -58,5 +58,13 @@ public function install(array $module_list, $enable_dependencies = TRUE);
    */
   public function uninstall(array $module_list, $uninstall_dependents = TRUE);
 
+  /**
+   * Determines which modules can be uninstalled.
+   *
+   * @param array $module_list
+   *   The modules to uninstall.
+   */
+  public function validateUninstall(array $module_list);
+
 }
 
diff --git a/core/modules/system/src/Form/ModulesUninstallForm.php b/core/modules/system/src/Form/ModulesUninstallForm.php
index 4285956..d969d90 100644
--- a/core/modules/system/src/Form/ModulesUninstallForm.php
+++ b/core/modules/system/src/Form/ModulesUninstallForm.php
@@ -8,6 +8,7 @@
 namespace Drupal\system\Form;
 
 use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Extension\ModuleInstallerInterface;
 use Drupal\Core\Form\FormBase;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\Core\KeyValueStore\KeyValueStoreExpirableInterface;
@@ -26,6 +27,13 @@ class ModulesUninstallForm extends FormBase {
   protected $moduleHandler;
 
   /**
+   * The module installer service.
+   *
+   * @var \Drupal\Core\Extension\ModuleInstallerInterface
+   */
+  protected $moduleInstaller;
+
+  /**
    * The expirable key value store.
    *
    * @var \Drupal\Core\KeyValueStore\KeyValueStoreExpirableInterface
@@ -38,6 +46,7 @@ class ModulesUninstallForm extends FormBase {
   public static function create(ContainerInterface $container) {
     return new static(
       $container->get('module_handler'),
+      $container->get('module_installer'),
       $container->get('keyvalue.expirable')->get('modules_uninstall')
     );
   }
@@ -47,11 +56,14 @@ public static function create(ContainerInterface $container) {
    *
    * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
    *   The module handler.
+   * @param \Drupal\Core\Extension\ModuleInstallerInterface $module_installer
+   *   The module installer.
    * @param \Drupal\Core\KeyValueStore\KeyValueStoreExpirableInterface $key_value_expirable
    *   The key value expirable factory.
    */
-  public function __construct(ModuleHandlerInterface $module_handler, KeyValueStoreExpirableInterface $key_value_expirable) {
+  public function __construct(ModuleHandlerInterface $module_handler, ModuleInstallerInterface $module_installer, KeyValueStoreExpirableInterface $key_value_expirable) {
     $this->moduleHandler = $module_handler;
+    $this->moduleInstaller = $module_installer;
     $this->keyValueExpirable = $key_value_expirable;
   }
 
@@ -72,6 +84,8 @@ public function buildForm(array $form, FormStateInterface $form_state) {
     // Get a list of disabled, installed modules.
     $modules = system_rebuild_module_data();
     $uninstallable = array_filter($modules, function ($module) use ($modules) {
+      // @todo use validateUninstall here also.
+      //$modules = $this->moduleInstaller->validateUninstall($modules);
       return empty($modules[$module->getName()]->info['required']) && drupal_get_installed_schema_version($module->getName()) > SCHEMA_UNINSTALLED;
     });