diff --git a/.changelog/4961.txt b/.changelog/4961.txt
new file mode 100644
index 00000000000..05a2d4782dc
--- /dev/null
+++ b/.changelog/4961.txt
@@ -0,0 +1,3 @@
+```release-note:enhancement
+composer: added field `maintenance_window` to resource `google_composer_environment` (beta)
+```
diff --git a/google/resource_composer_environment_test.go b/google/resource_composer_environment_test.go
index 225a910cc84..a3c71eaa9ea 100644
--- a/google/resource_composer_environment_test.go
+++ b/google/resource_composer_environment_test.go
@@ -446,7 +446,6 @@ resource "google_composer_environment" "test" {
 			}
 		}
 	}
-
 	depends_on = [google_project_iam_member.composer-worker]
 }
 
diff --git a/website/docs/r/composer_environment.html.markdown b/website/docs/r/composer_environment.html.markdown
index 18a4459ae6f..f93ca38f04f 100644
--- a/website/docs/r/composer_environment.html.markdown
+++ b/website/docs/r/composer_environment.html.markdown
@@ -182,6 +182,10 @@ The `config` block supports:
 * `encryption_config` -
   (Optional, [Beta](https://terraform.io/docs/providers/google/guides/provider_versions.html))
   The encryption options for the Cloud Composer environment and its dependencies.
+  
+* `maintenance_window` -
+  (Optional, [Beta](https://terraform.io/docs/providers/google/guides/provider_versions.html))
+  The configuration settings for Cloud Composer maintenance window.
 
 The `node_config` block supports:
 
@@ -410,6 +414,22 @@ The `encryption_config` block supports:
   be the fully qualified resource name, 
   i.e. projects/project-id/locations/location/keyRings/keyring/cryptoKeys/key. Cannot be updated.
 
+The `maintenance_window` block supports:
+
+* `start_time` -
+  (Required)
+  Start time of the first recurrence of the maintenance window.
+
+* `end_time` -
+  (Required)
+  Maintenance window end time. It is used only to calculate the duration of the maintenance window.
+  The value for end-time must be in the future, relative to 'start_time'.
+
+* `recurrence` -
+  (Required)
+  Maintenance window recurrence. Format is a subset of RFC-5545 (https://tools.ietf.org/html/rfc5545) 'RRULE'.
+  The only allowed values for 'FREQ' field are 'FREQ=DAILY' and 'FREQ=WEEKLY;BYDAY=...'.
+  Example values: 'FREQ=WEEKLY;BYDAY=TU,WE', 'FREQ=DAILY'.
 
 ## Attributes Reference