diff --git a/.changelog/3646.txt b/.changelog/3646.txt
new file mode 100644
index 00000000000..fe69b0e1abb
--- /dev/null
+++ b/.changelog/3646.txt
@@ -0,0 +1,3 @@
+```release-note:enhancement
+app_engine: added the option to specify `database_type` in `google_app_engine_application`
+```
diff --git a/google/resource_app_engine_application.go b/google/resource_app_engine_application.go
index 5163480bb1a..510d99caa22 100644
--- a/google/resource_app_engine_application.go
+++ b/google/resource_app_engine_application.go
@@ -59,6 +59,15 @@ func resourceAppEngineApplication() *schema.Resource {
 				}, false),
 				Computed: true,
 			},
+			"database_type": {
+				Type:     schema.TypeString,
+				Optional: true,
+				ValidateFunc: validation.StringInSlice([]string{
+					"CLOUD_FIRESTORE",
+					"CLOUD_DATASTORE_COMPATIBILITY",
+				}, false),
+				Computed: true,
+			},
 			"feature_settings": {
 				Type:     schema.TypeList,
 				Optional: true,
@@ -221,6 +230,7 @@ func resourceAppEngineApplicationRead(d *schema.ResourceData, meta interface{})
 	d.Set("app_id", app.Id)
 	d.Set("serving_status", app.ServingStatus)
 	d.Set("gcr_domain", app.GcrDomain)
+	d.Set("database_type", app.DatabaseType)
 	d.Set("project", pid)
 	dispatchRules, err := flattenAppEngineApplicationDispatchRules(app.DispatchRules)
 	if err != nil {
@@ -265,7 +275,7 @@ func resourceAppEngineApplicationUpdate(d *schema.ResourceData, meta interface{}
 	defer mutexKV.Unlock(lockName)
 
 	log.Printf("[DEBUG] Updating App Engine App")
-	op, err := config.clientAppEngine.Apps.Patch(pid, app).UpdateMask("authDomain,servingStatus,featureSettings.splitHealthChecks,iap").Do()
+	op, err := config.clientAppEngine.Apps.Patch(pid, app).UpdateMask("authDomain,databaseType,servingStatus,featureSettings.splitHealthChecks,iap").Do()
 	if err != nil {
 		return fmt.Errorf("Error updating App Engine application: %s", err.Error())
 	}
@@ -291,6 +301,7 @@ func expandAppEngineApplication(d *schema.ResourceData, project string) (*appeng
 		LocationId:    d.Get("location_id").(string),
 		Id:            project,
 		GcrDomain:     d.Get("gcr_domain").(string),
+		DatabaseType:  d.Get("database_type").(string),
 		ServingStatus: d.Get("serving_status").(string),
 	}
 	featureSettings, err := expandAppEngineApplicationFeatureSettings(d)
diff --git a/google/resource_app_engine_application_test.go b/google/resource_app_engine_application_test.go
index 405ce7bbc87..b5400a235d0 100644
--- a/google/resource_app_engine_application_test.go
+++ b/google/resource_app_engine_application_test.go
@@ -101,6 +101,7 @@ resource "google_app_engine_application" "acceptance" {
   project        = google_project.acceptance.project_id
   auth_domain    = "hashicorptest.com"
   location_id    = "us-central"
+  database_type  = "CLOUD_DATASTORE_COMPATIBILITY"
   serving_status = "SERVING"
 }
 `, pid, pid, org)
@@ -118,6 +119,7 @@ resource "google_app_engine_application" "acceptance" {
   project        = google_project.acceptance.project_id
   auth_domain    = "tf-test.club"
   location_id    = "us-central"
+  database_type  = "CLOUD_DATASTORE_COMPATIBILITY"
   serving_status = "USER_DISABLED"
 }
 `, pid, pid, org)
diff --git a/website/docs/r/app_engine_application.html.markdown b/website/docs/r/app_engine_application.html.markdown
index 1bf01beb71d..e6390c84692 100644
--- a/website/docs/r/app_engine_application.html.markdown
+++ b/website/docs/r/app_engine_application.html.markdown
@@ -47,6 +47,8 @@ The following arguments are supported:
 
 * `auth_domain` - (Optional) The domain to authenticate users with when using App Engine's User API.
 
+* `database_type` - (Optional) The type of the Cloud Firestore or Cloud Datastore database associated with this application.
+
 * `serving_status` - (Optional) The serving status of the app.
 
 * `feature_settings` - (Optional) A block of optional settings to configure specific App Engine features: