diff --git a/.changelog/3203.txt b/.changelog/3203.txt
new file mode 100644
index 0000000000..795cfbd49f
--- /dev/null
+++ b/.changelog/3203.txt
@@ -0,0 +1,3 @@
+```release-note:enhancement
+resource/tencentcloud_cynosdb_cluster: optimize ro group sg
+```
\ No newline at end of file
diff --git a/tencentcloud/services/cynosdb/extension_cynosdb.go b/tencentcloud/services/cynosdb/extension_cynosdb.go
index c895af0be4..0ff335ba07 100644
--- a/tencentcloud/services/cynosdb/extension_cynosdb.go
+++ b/tencentcloud/services/cynosdb/extension_cynosdb.go
@@ -26,8 +26,9 @@ const (
 	CYNOSDB_DEFAULT_OFFSET = 0
 	CYNOSDB_MAX_LIMIT      = 100
 
-	CYNOSDB_INSGRP_HA = "ha"
-	CYNOSDB_INSGRP_RO = "ro"
+	CYNOSDB_INSGRP_HA       = "ha"
+	CYNOSDB_INSGRP_RO       = "ro"
+	CYNOSDB_INSGRP_SINGLERO = "singleRo"
 
 	// 0-成功，1-失败，2-处理中
 	CYNOSDB_FLOW_STATUS_SUCCESSFUL = "0"
diff --git a/tencentcloud/services/cynosdb/resource_tc_cynosdb_cluster.go b/tencentcloud/services/cynosdb/resource_tc_cynosdb_cluster.go
index 4b3d883687..5d8da5589b 100644
--- a/tencentcloud/services/cynosdb/resource_tc_cynosdb_cluster.go
+++ b/tencentcloud/services/cynosdb/resource_tc_cynosdb_cluster.go
@@ -337,7 +337,7 @@ func resourceTencentCloudCynosdbClusterCreate(d *schema.ResourceData, meta inter
 	for _, insGrp := range insGrps.Response.InstanceGrpInfoList {
 		if *insGrp.Type == CYNOSDB_INSGRP_HA {
 			rwGroupId = *insGrp.InstanceGrpId
-		} else if *insGrp.Type == CYNOSDB_INSGRP_RO {
+		} else if *insGrp.Type == CYNOSDB_INSGRP_RO || *insGrp.Type == CYNOSDB_INSGRP_SINGLERO {
 			roGroupIds = append(roGroupIds, *insGrp.InstanceGrpId)
 		}
 	}
@@ -499,7 +499,7 @@ func resourceTencentCloudCynosdbClusterRead(d *schema.ResourceData, meta interfa
 				"ip":   *insGrp.Vip,
 				"port": *insGrp.Vport,
 			})
-		} else if *insGrp.Type == CYNOSDB_INSGRP_RO {
+		} else if *insGrp.Type == CYNOSDB_INSGRP_RO || *insGrp.Type == CYNOSDB_INSGRP_SINGLERO {
 			roGroupId = *insGrp.InstanceGrpId
 			_ = d.Set("ro_group_id", roGroupId)
 			for _, roIns := range insGrp.InstanceSet {