diff --git a/doc/install/install-from-source.md b/doc/install/install-from-source.md
index 8efa20a374..c9764e548c 100644
--- a/doc/install/install-from-source.md
+++ b/doc/install/install-from-source.md
@@ -174,7 +174,7 @@ One may add the following arguments to `cmake`:
 | -DCUDA_TOOLKIT_ROOT_DIR=<value> | Path         | Detected automatically | The path to the CUDA toolkit directory. |
 | -DUSE_ROCM_TOOLKIT=<value> | `TRUE` or `FALSE` | `FALSE`       | If `TRUE`, Build GPU support with ROCM toolkit. |
 | -DROCM_ROOT=<value> | Path         | Detected automatically | The path to the ROCM toolkit directory. |
-| -DLAMMPS_VERSION_NUMBER=<value> | Number         | `20201029` | Only neccessary for LAMMPS built-in mode. The version number of LAMMPS (yyyymmdd). |
+| -DLAMMPS_VERSION_NUMBER=<value> | Number         | `20210929` | Only neccessary for LAMMPS built-in mode. The version number of LAMMPS (yyyymmdd). |
 | -DLAMMPS_SOURCE_ROOT=<value> | Path         | - | Only neccessary for LAMMPS plugin mode. The path to the LAMMPS source code (later than 8Apr2021). If not assigned, the plugin mode will not be enabled. |
 
 If the cmake has executed successfully, then 
diff --git a/doc/install/install-lammps.md b/doc/install/install-lammps.md
index d86a7e909f..d50be897ee 100644
--- a/doc/install/install-lammps.md
+++ b/doc/install/install-lammps.md
@@ -12,12 +12,12 @@ make lammps
 DeePMD-kit will generate a module called `USER-DEEPMD` in the `build` directory. If you need low precision version, move `env_low.sh` to `env.sh` in the directory. Now download the LAMMPS code (`29Oct2020` or later), and uncompress it:
 ```bash
 cd /some/workspace
-wget https://github.com/lammps/lammps/archive/stable_29Oct2020.tar.gz
-tar xf stable_29Oct2020.tar.gz
+wget https://github.com/lammps/lammps/archive/stable_29Sep2021.tar.gz
+tar xf stable_29Sep2021.tar.gz
 ```
-The source code of LAMMPS is stored in directory `lammps-stable_29Oct2020`. Now go into the LAMMPS code and copy the DeePMD-kit module like this
+The source code of LAMMPS is stored in directory `lammps-stable_29Sep2021`. Now go into the LAMMPS code and copy the DeePMD-kit module like this
 ```bash
-cd lammps-stable_29Oct2020/src/
+cd lammps-stable_29Sep2021/src/
 cp -r $deepmd_source_dir/source/build/USER-DEEPMD .
 ```
 Now build LAMMPS
@@ -43,13 +43,13 @@ Starting from `8Apr2021`, LAMMPS also provides a plugin mode, allowing one build
 Now download the LAMMPS code (`8Apr2021` or later), and uncompress it:
 ```bash
 cd /some/workspace
-wget https://github.com/lammps/lammps/archive/patch_30Jul2021.tar.gz
-tar xf patch_30Jul2021.tar.gz
+wget https://github.com/lammps/lammps/archive/stable_29Sep2021.tar.gz
+tar xf stable_29Sep2021.tar.gz
 ```
-The source code of LAMMPS is stored in directory `lammps-patch_30Jul2021`. Now go into the LAMMPS code and create a directory called `build`
+The source code of LAMMPS is stored in directory `lammps-stable_29Sep2021`. Now go into the LAMMPS code and create a directory called `build`
 ```bash
-mkdir -p lammps-patch_30Jul2021/build/
-cd lammps-patch_30Jul2021/build/
+mkdir -p lammps-stable_29Sep2021/build/
+cd lammps-stable_29Sep2021/build/
 ```
 Now build LAMMPS. Note that `PLUGIN` and `KSPACE` package must be enabled, and `BUILD_SHARED_LIBS` must be set to `yes`. You can install any other package you want.
 ```bash
diff --git a/source/install/build_cc.sh b/source/install/build_cc.sh
index 16a269404d..c7e7686812 100755
--- a/source/install/build_cc.sh
+++ b/source/install/build_cc.sh
@@ -20,7 +20,7 @@ NPROC=$(nproc --all)
 BUILD_TMP_DIR=${SCRIPT_PATH}/../build
 mkdir -p ${BUILD_TMP_DIR}
 cd ${BUILD_TMP_DIR}
-cmake -DCMAKE_INSTALL_PREFIX=${INSTALL_PREFIX} -DINSTALL_TENSORFLOW=TRUE ${CUDA_ARGS} -DLAMMPS_VERSION=patch_30Jul2021 -DUSE_TTM=TRUE ..
+cmake -DCMAKE_INSTALL_PREFIX=${INSTALL_PREFIX} -DINSTALL_TENSORFLOW=TRUE ${CUDA_ARGS} -DLAMMPS_VERSION=stable_29Sep2021 -DUSE_TTM=TRUE ..
 make -j${NPROC}
 make install
 
diff --git a/source/install/build_lammps.sh b/source/install/build_lammps.sh
index c11aa2c733..912f577979 100755
--- a/source/install/build_lammps.sh
+++ b/source/install/build_lammps.sh
@@ -15,7 +15,7 @@ BUILD_TMP_DIR=${SCRIPT_PATH}/../build_lammps
 mkdir -p ${BUILD_TMP_DIR}
 cd ${BUILD_TMP_DIR}
 # download LAMMMPS
-LAMMPS_VERSION=patch_30Jul2021
+LAMMPS_VERSION=stable_29Sep2021
 if [ ! -d "lammps-${LAMMPS_VERSION}" ]
 then
 	curl -L -o lammps.tar.gz https://github.com/lammps/lammps/archive/refs/tags/${LAMMPS_VERSION}.tar.gz
diff --git a/source/lmp/CMakeLists.txt b/source/lmp/CMakeLists.txt
index bb89a6357b..970959c678 100644
--- a/source/lmp/CMakeLists.txt
+++ b/source/lmp/CMakeLists.txt
@@ -1,7 +1,7 @@
 add_subdirectory(plugin)
 if (NOT DEFINED LAMMPS_VERSION_NUMBER)
-    # set the default to 29 Oct 2020
-    set(LAMMPS_VERSION_NUMBER 20201029)
+    # set the default to stable_29Sep2021
+    set(LAMMPS_VERSION_NUMBER 20210929)
 endif()
 message(STATUS "LAMMPS version is ${LAMMPS_VERSION_NUMBER}")