diff --git a/.changelog/4778.txt b/.changelog/4778.txt
new file mode 100644
index 0000000000..0b12793a4f
--- /dev/null
+++ b/.changelog/4778.txt
@@ -0,0 +1,3 @@
+```release-note:bug
+compute: added mutex in `google_compute_metadata_item` to reduce retries + quota errors
+```
diff --git a/google-beta/resource_compute_project_metadata_item.go b/google-beta/resource_compute_project_metadata_item.go
index 0e4572342b..48bc92e01a 100644
--- a/google-beta/resource_compute_project_metadata_item.go
+++ b/google-beta/resource_compute_project_metadata_item.go
@@ -170,6 +170,10 @@ func resourceComputeProjectMetadataItemDelete(d *schema.ResourceData, meta inter
 
 func updateComputeCommonInstanceMetadata(config *Config, projectID, key, userAgent string, afterVal *string, timeout time.Duration, failIfPresent metadataPresentBehavior) error {
 	updateMD := func() error {
+		lockName := fmt.Sprintf("projects/%s/commoninstancemetadata", projectID)
+		mutexKV.Lock(lockName)
+		defer mutexKV.Unlock(lockName)
+
 		log.Printf("[DEBUG] Loading project metadata: %s", projectID)
 		project, err := config.NewComputeClient(userAgent).Projects.Get(projectID).Do()
 		if err != nil {