diff --git a/mia_core/templatetags.py b/mia_core/templatetags.py
new file mode 100644
index 0000000..1580090
--- /dev/null
+++ b/mia_core/templatetags.py
@@ -0,0 +1,32 @@
+# The template tags of the Mia project.
+#   by imacat <imacat@mail.imacat.idv.tw>, 2020/7/1
+
+#  Copyright (c) 2020 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+
+from django import template
+register = template.Library()
+
+
+@register.simple_tag(takes_context=True)
+def setvar(context, key, value):
+    """Sets a variable in the template.
+
+    Args:
+        context (Context): the context
+        key (str): The variable name
+        value (str): The variable value
+    """
+    context.dicts[0][key] = value
+    return ""