diff --git a/.gitignore b/.gitignore
index 1e5c982f9..461a08230 100644
--- a/.gitignore
+++ b/.gitignore
@@ -94,6 +94,9 @@ venv.bak/
 .spyderproject
 .spyproject
 
+# Pycharm project setting
+.idea/
+
 # Rope project settings
 .ropeproject
 
diff --git a/docs/index.rst b/docs/index.rst
index a5058c5b4..1a5578cc6 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -125,6 +125,7 @@ Topic guides provide in-depth explanations of specific topics.
    topic/authenticator-configuration
    topic/escape-hatch
    topic/idle-culler
+   topic/env-var-for-tljh-service
 
 
 Troubleshooting
diff --git a/docs/topic/env-var-for-tljh-service.rst b/docs/topic/env-var-for-tljh-service.rst
new file mode 100644
index 000000000..63b17a9d3
--- /dev/null
+++ b/docs/topic/env-var-for-tljh-service.rst
@@ -0,0 +1,57 @@
+.. _topic/env-var-for-tljh-service:
+
+===========================================================
+Locale Setting & Other Environment Variables for Jupyterhub
+===========================================================
+
+Sometimes you need to run TLJH in the other language environment rather than English.
+This will cause some unexpected problems.
+
+e.g.
+
+- The file whose name is not English can not display properly
+- Can not open or create the file whose name is not English
+
+
+ | You may find that no matter what you set in the shell, you will find that the locale is right in the shell only. And in the jupyter notebook/lab which is spawned by TLJH nothing has been changed.
+
+*The reason is that TLJH starts jupyterhub as a systemed service.*
+
+*As a systemed service unit, its environment variables should be set in its config.*
+
+
+So, we provide a convenient way to set the locale or other environment variables for the service.
+We will create a config ``environment_for_system_service.conf`` in the ``/srv/src/tljh`` when the installer is running.
+You can add or modify any environment variables in it.
+
+e.g.
+
+.. code-block:: bash
+
+    LANG=zh_CN.UTF-8
+
+**Notice that before you modify the language setting in the conf, install the related fonts and packages first.**
+
+
+
+After you do some changes, you should use
+
+.. code-block:: bash
+
+    sudo systemctl daemon-reload
+
+to reload jupyterhub.service`s config.
+
+and
+
+.. code-block:: bash
+
+    sudo tljh-config reload hub
+
+to reload tljh.
+
+**You should be aware that everything set in ``environment_for_system_service.conf`` is only for the ``jupyterhub.service`` .**
+
+It means that you`d better just add the environment variables which the jupyterhub needs instead of all the environment variables in your environment.
+
+
diff --git a/tljh/installer.py b/tljh/installer.py
index 05055e260..b2b18cfc9 100644
--- a/tljh/installer.py
+++ b/tljh/installer.py
@@ -38,6 +38,7 @@
 
 logger = logging.getLogger("tljh")
 
+
 def ensure_node():
     """
     Ensure nodejs from nodesource is installed
@@ -100,6 +101,7 @@ def ensure_node():
     apt.add_source('nodesource', 'https://deb.nodesource.com/node_10.x', 'main')
     apt.install_packages(['nodejs'])
 
+
 def remove_chp():
     """
     Ensure CHP is not running
@@ -134,11 +136,15 @@ def ensure_jupyterhub_service(prefix):
     with open(os.path.join(HERE, 'systemd-units', 'jupyterhub.service')) as f:
         hub_unit_template = f.read()
 
-
     with open(os.path.join(HERE, 'systemd-units', 'traefik.service')) as f:
         traefik_unit_template = f.read()
 
-    #Set up proxy / hub secret token if it is not already setup
+    # Get the default locale setting
+    with open(os.path.join(HERE, 'environment_for_system_service.conf'), 'a+', encoding='utf-8') as f:
+        r = os.popen("locale").read()
+        f.write(r)
+
+    # Set up proxy / hub secret token if it is not already setup
     proxy_secret_path = os.path.join(STATE_DIR, 'traefik-api.secret')
     if not os.path.exists(proxy_secret_path):
         with open(proxy_secret_path, 'w') as f:
@@ -149,6 +155,7 @@ def ensure_jupyterhub_service(prefix):
     unit_params = dict(
         python_interpreter_path=sys.executable,
         jupyterhub_config_path=os.path.join(HERE, 'jupyterhub_config.py'),
+        env_conf=os.path.join(HERE, 'environment_for_system_service.conf'),
         install_prefix=INSTALL_PREFIX,
     )
     systemd.install_unit('jupyterhub.service', hub_unit_template.format(**unit_params))
@@ -316,9 +323,9 @@ def ensure_jupyterhub_running(times=20):
             # Everything else should immediately abort
             raise
         except requests.ConnectionError:
-                # Hub isn't up yet, sleep & loop
-                time.sleep(1)
-                continue
+            # Hub isn't up yet, sleep & loop
+            time.sleep(1)
+            continue
         except Exception:
             # Everything else should immediately abort
             raise
diff --git a/tljh/systemd-units/jupyterhub.service b/tljh/systemd-units/jupyterhub.service
index 477d04b76..453b05086 100644
--- a/tljh/systemd-units/jupyterhub.service
+++ b/tljh/systemd-units/jupyterhub.service
@@ -17,6 +17,7 @@ PrivateDevices=yes
 ProtectKernelTunables=yes
 ProtectKernelModules=yes
 Environment=TLJH_INSTALL_PREFIX={install_prefix}
+EnvironmentFile={env_conf}
 # Run upgrade-db before starting, in case Hub version has changed
 # This is a no-op when no db exists or no upgrades are needed
 ExecStart={python_interpreter_path} -m jupyterhub.app -f {jupyterhub_config_path} --upgrade-db