diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 8cd2d74ea32d1a1a68e145ad0f04c31cd48f6b6e..52197e37ff0467fb5fe985e739383291490fa28a 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -62,7 +62,6 @@ jobs:
           - 'windows-2019'
           - 'macos-10.15'
         python:
-          - '3.6'
           - '3.7'
           - '3.8'
           - '3.9'
@@ -92,8 +91,6 @@ jobs:
             architecture: x86
           - os: macos-10.15
             architecture: AMD64
-          - python: '3.6'
-            architecture: arm64
           - python: '3.7'
             architecture: arm64
 
@@ -139,7 +136,6 @@ jobs:
           - 'windows-2019'
           - 'macos-10.15'
         python:
-          - '3.6'
           - '3.7'
           - '3.8'
           - '3.9'
@@ -169,8 +165,6 @@ jobs:
             architecture: x86
           - os: macos-10.15
             architecture: AMD64
-          - python: '3.6'
-            architecture: arm64
           - python: '3.7'
             architecture: arm64
 
diff --git a/.github/workflows/release_test.yml b/.github/workflows/release_test.yml
index d62f682a967730c80f269f3ea6b577cbae7ed8c4..c2a7f33bd5492859ea6661c35e67f4a27fc819ed 100644
--- a/.github/workflows/release_test.yml
+++ b/.github/workflows/release_test.yml
@@ -52,7 +52,6 @@ jobs:
           - 'windows-2019'
           - 'macos-10.15'
         python:
-          - '3.6'
           - '3.7'
           - '3.8'
           - '3.9'
@@ -82,8 +81,6 @@ jobs:
             architecture: x86
           - os: macos-10.15
             architecture: AMD64
-          - python: '3.6'
-            architecture: arm64
           - python: '3.7'
             architecture: arm64
 
diff --git a/.github/workflows/run.yml b/.github/workflows/run.yml
index 22035c855c8e25b0d29e7f1a1032461e095bf74d..daba9f7d56986b6863e251981422aed02471bb4e 100644
--- a/.github/workflows/run.yml
+++ b/.github/workflows/run.yml
@@ -15,7 +15,6 @@ jobs:
         os:
           - 'ubuntu-18.04'
         python-version:
-          - '3.6'
           - '3.7'
           - '3.8'
           - '3.9'
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 013659ea42e29c39c184a539a52cff5e6f99839d..f0100aa6cea3de2f3403b7dce7ade6f0b39a6b6f 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -21,7 +21,6 @@ jobs:
           - 'windows-2019'  # need to be fixed, see: https://github.com/opendilab/treevalue/issues/41
           - 'macos-10.15'
         python-version:
-          - '3.6'
           - '3.7'
           - '3.8'
           - '3.9'
diff --git a/setup.py b/setup.py
index 639fb1a8c9dfb4d5d3f1af7f4e0ad9f839df76e0..393ffc2f60e3fd41c8a606defc3c7af7905859c1 100644
--- a/setup.py
+++ b/setup.py
@@ -60,7 +60,7 @@ setup(
     url='https://github.com/HansBug/treevalue',
 
     # environment
-    python_requires=">=3.6",
+    python_requires=">=3.7",
     ext_modules=cythonize(
         find_pyx(),
         language_level=3,
@@ -77,7 +77,6 @@ setup(
         'License :: OSI Approved :: Apache Software License',
         'Programming Language :: Python',
         'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8',
         'Programming Language :: Python :: 3.9',