diff --git a/tools/images_packer/README.md b/tools/images_packer/README.md
index 6fc53a094..e0be9e8db 100644
--- a/tools/images_packer/README.md
+++ b/tools/images_packer/README.md
@@ -133,7 +133,7 @@ This image builder requires latest ota-client to be installed/accessable. The re
 ```bash
 # current folder layout: venv ota-client
 (venv) $ cd ota-client
-(venv) $ sudo -E env PATH=$PATH python3 -m tools.image_packer build-cache-src --image-dir=./images_dir --output=t2.tar
+(venv) $ sudo -E env PATH=$PATH python3 -m tools.images_packer build-cache-src --image-dir=./images_dir --output=t2.tar
 ```
 
 This will build the external cache source image with images listed in `./images_dir`, and export the built image as `t2.tar` tar archive.
@@ -143,17 +143,17 @@ This will build the external cache source image with images listed in `./images_
 ```bash
 # current folder layout: venv ota-client
 (venv) $ cd ota-client
-(venv) $ sudo -E env PATH=$PATH python3 -m tools.image_packer build-offline-ota-imgs-bundle --image=p1:p1_image.tgz:ver_20230808 --image=p2:p2_image.tgz:ver_20230808 --output=t2.tar
+(venv) $ sudo -E env PATH=$PATH python3 -m tools.images_packer build-offline-ota-imgs-bundle --image=p1:p1_image.tgz:ver_20230808 --image=p2:p2_image.tgz:ver_20230808 --output=t2.tar
 ```
 
 This will build the offline OTA image with `p1_image.tgz` and `p2_image.tgz`, which are for ECU `p1` and `p2`, and export the built image as `t2.tar` tar archive.
 
-#### Usage 3: Build the external cache source image and create external cache source dev
+#### Usage 3: Build the external cache source image and create external cache source device
 
 ```bash
 # current folder layout: venv ota-client
 (venv) $ cd ota-client
-(venv) $ sudo -E env PATH=$PATH python3 -m tools.image_packer build-cache-src  --image-dir=./images_dir --write-to=/dev/<target_dev>
+(venv) $ sudo -E env PATH=$PATH python3 -m tools.images_packer build-cache-src  --image-dir=./images_dir --write-to=/dev/<target_dev>
 ```
 
 This will build the external cache source image OTA images listed in the `./images_dir`, and prepare the `/dev/<target_dev>` as external cache source device(ext4 filesystem labelled with `ota_cache_src`) with image rootfs exported to the filesystem on `/dev/<target_device>`.
@@ -183,7 +183,7 @@ optional arguments:
 ### `build-offline-ota-imgs-bundle` subcommand
 
 ```text
-usage: images_packer build-offline-ota-imgs-bundle [-h] --image <ECU_NAME>:<IMAGE_PATH>[:<IMAGE_VERSION>] [-o <OUTPUT_FILE_PATH>]
+usage: images_packer build-offline-ota-imgs-bundle [-h] --image <ECU_NAME>:<IMAGE_PATH>[:<IMAGE_VERSION>] -o <OUTPUT_FILE_PATH>
 
 build OTA image bundle for offline OTA use.
 
@@ -191,6 +191,7 @@ optional arguments:
   -h, --help            show this help message and exit
   --image <ECU_NAME>:<IMAGE_PATH>[:<IMAGE_VERSION>]
                         OTA image for <ECU_ID> as tar archive(compressed or uncompressed), this option can be used multiple times to include multiple images.
+                        NOTE: if multiple OTA target image is specified for the same ECU, the later one will override the previous set one.
   -o <OUTPUT_FILE_PATH>, --output <OUTPUT_FILE_PATH>
                         save the generated image bundle tar archive to <OUTPUT_FILE_PATH>.
 ```
diff --git a/tools/images_packer/__main__.py b/tools/images_packer/__main__.py
index 867d3f144..c8779720f 100644
--- a/tools/images_packer/__main__.py
+++ b/tools/images_packer/__main__.py
@@ -69,6 +69,13 @@ def main_build_offline_ota_image_bundle(args: argparse.Namespace):
                     image_version=_image_version,
                 )
             )
+            if _ecu_id in image_files:
+                logger.warning(
+                    (
+                        f"override previously set OTA target image for ECU@{_ecu_id} "
+                        f"from {image_files[_ecu_id]} to {_image_fpath}"
+                    )
+                )
             image_files[_ecu_id] = _image_fpath
         else:
             logger.warning(f"ignore illegal image pair: {raw_pair}")
@@ -233,7 +240,9 @@ def command_build_offline_ota_image_bundle(
         "--image",
         help=(
             "OTA image for <ECU_ID> as tar archive(compressed or uncompressed), "
-            "this option can be used multiple times to include multiple images."
+            "this option can be used multiple times to include multiple images. \n"
+            "NOTE: if multiple OTA target image is specified for the same ECU, the later one "
+            "will override the previous set one."
         ),
         required=True,
         metavar="<ECU_NAME>:<IMAGE_PATH>[:<IMAGE_VERSION>]",