diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index c0e0902aa4..69503dd96a 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -60,12 +60,6 @@ jobs:
             mmcv: 1.8.0+cu101
             torchvision: 0.9.0+cu101
             cuda_arch: "7.0"
-          - python-version: 3.9
-            torch: 1.8.0+cu101
-            torch_version: torch1.8.0
-            mmcv: 1.8.0+cu101
-            torchvision: 0.9.0+cu101
-            cuda_arch: "7.0"
 
     steps:
       - uses: actions/checkout@v2
diff --git a/requirements/docs.txt b/requirements/docs.txt
index fece607fe6..40f8c9ff25 100644
--- a/requirements/docs.txt
+++ b/requirements/docs.txt
@@ -1,6 +1,8 @@
+docutils==0.16.0
 m2r
+myst-parser
 opencv-python
-recommonmark
-sphinx
+sphinx==4.0.2
 sphinx_markdown_tables
-sphinx_rtd_theme
+sphinx_rtd_theme==0.5.2
+torch
diff --git a/setup.py b/setup.py
index 99fb3cd24a..28ec46cf2b 100644
--- a/setup.py
+++ b/setup.py
@@ -210,7 +210,6 @@ def add_mim_extention():
             'Programming Language :: Python :: 3',
             'Programming Language :: Python :: 3.6',
             'Programming Language :: Python :: 3.7',
-            'Programming Language :: Python :: 3.9',
         ],
         license='Apache License 2.0',
         setup_requires=parse_requirements('requirements/build.txt'),