diff --git a/.changelog/3650.txt b/.changelog/3650.txt
new file mode 100644
index 0000000000..b0046fd3f3
--- /dev/null
+++ b/.changelog/3650.txt
@@ -0,0 +1,3 @@
+```release-note:enhancement
+resource/tencentcloud_clb_attachment: update doc
+```
\ No newline at end of file
diff --git a/tencentcloud/services/clb/resource_tc_clb_attachment.md b/tencentcloud/services/clb/resource_tc_clb_attachment.md
index d9ff2aa050..169dcdd70b 100644
--- a/tencentcloud/services/clb/resource_tc_clb_attachment.md
+++ b/tencentcloud/services/clb/resource_tc_clb_attachment.md
@@ -130,3 +130,9 @@ If use domain & url
 ```
 $ terraform import tencentcloud_clb_attachment.example test.com,/path#lbl-hh141sn9#lb-7a0t6zqb
 ```
+
+Of if use layer-4 forwarding rule
+
+```
+$ terraform import tencentcloud_clb_attachment.example ""#lbl-hh141sn9#lb-7a0t6zqb
+```
diff --git a/website/docs/r/clb_attachment.html.markdown b/website/docs/r/clb_attachment.html.markdown
index 80a0192492..d54f85f33c 100644
--- a/website/docs/r/clb_attachment.html.markdown
+++ b/website/docs/r/clb_attachment.html.markdown
@@ -168,3 +168,9 @@ If use domain & url
 $ terraform import tencentcloud_clb_attachment.example test.com,/path#lbl-hh141sn9#lb-7a0t6zqb
 ```
 
+Of if use layer-4 forwarding rule
+
+```
+$ terraform import tencentcloud_clb_attachment.example ""#lbl-hh141sn9#lb-7a0t6zqb
+```
+