diff --git a/.changelog/3155.txt b/.changelog/3155.txt
new file mode 100644
index 0000000000..44394c6bbf
--- /dev/null
+++ b/.changelog/3155.txt
@@ -0,0 +1,3 @@
+```release-note:enhancement
+resource/tencentcloud_cos_bucket_policy: update doc
+```
\ No newline at end of file
diff --git a/tencentcloud/services/cos/resource_tc_cos_bucket_policy.md b/tencentcloud/services/cos/resource_tc_cos_bucket_policy.md
index 7fc9c6f47d..39ac522f21 100644
--- a/tencentcloud/services/cos/resource_tc_cos_bucket_policy.md
+++ b/tencentcloud/services/cos/resource_tc_cos_bucket_policy.md
@@ -3,9 +3,19 @@ Provides a COS resource to create a COS bucket policy and set its attributes.
 Example Usage
 
 ```hcl
-resource "tencentcloud_cos_bucket_policy" "cos_policy" {
-  bucket = "mycos-1258798060"
+data "tencentcloud_user_info" "info" {}
 
+locals {
+  app_id = data.tencentcloud_user_info.info.app_id
+}
+
+resource "tencentcloud_cos_bucket" "example" {
+  bucket = "private-bucket-${local.app_id}"
+  acl    = "private"
+}
+
+resource "tencentcloud_cos_bucket_policy" "example" {
+  bucket = tencentcloud_cos_bucket.example.id
   policy = <<EOF
 {
   "version": "2.0",
@@ -22,7 +32,7 @@ resource "tencentcloud_cos_bucket_policy" "cos_policy" {
       ],
       "Effect": "allow",
       "Resource": [
-        "qcs::cos:<bucket region>:uid/<your-account-id>:<bucket name>/*"
+        "qcs::cos:<bucket region>:uid/<your-appid-id>:<your-bucket-name>/*"
       ]
     }
   ]
@@ -36,5 +46,5 @@ Import
 COS bucket policy can be imported, e.g.
 
 ```
-$ terraform import tencentcloud_cos_bucket_policy.bucket bucket-name
+$ terraform import tencentcloud_cos_bucket_policy.example private-bucket-1309118521
 ```
\ No newline at end of file
diff --git a/website/docs/r/cos_bucket_policy.html.markdown b/website/docs/r/cos_bucket_policy.html.markdown
index 2b6c9a6af2..32e076b381 100644
--- a/website/docs/r/cos_bucket_policy.html.markdown
+++ b/website/docs/r/cos_bucket_policy.html.markdown
@@ -14,9 +14,19 @@ Provides a COS resource to create a COS bucket policy and set its attributes.
 ## Example Usage
 
 ```hcl
-resource "tencentcloud_cos_bucket_policy" "cos_policy" {
-  bucket = "mycos-1258798060"
+data "tencentcloud_user_info" "info" {}
 
+locals {
+  app_id = data.tencentcloud_user_info.info.app_id
+}
+
+resource "tencentcloud_cos_bucket" "example" {
+  bucket = "private-bucket-${local.app_id}"
+  acl    = "private"
+}
+
+resource "tencentcloud_cos_bucket_policy" "example" {
+  bucket = tencentcloud_cos_bucket.example.id
   policy = <<EOF
 {
   "version": "2.0",
@@ -33,7 +43,7 @@ resource "tencentcloud_cos_bucket_policy" "cos_policy" {
       ],
       "Effect": "allow",
       "Resource": [
-        "qcs::cos:<bucket region>:uid/<your-account-id>:<bucket name>/*"
+        "qcs::cos:<bucket region>:uid/<your-appid-id>:<your-bucket-name>/*"
       ]
     }
   ]
@@ -62,6 +72,6 @@ In addition to all arguments above, the following attributes are exported:
 COS bucket policy can be imported, e.g.
 
 ```
-$ terraform import tencentcloud_cos_bucket_policy.bucket bucket-name
+$ terraform import tencentcloud_cos_bucket_policy.example private-bucket-1309118521
 ```