diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 280af4335..c219c3860 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,7 +11,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        python-version: [2.7, 3.7, 3.8, 3.9]
+        python-version: ["2.7", "3.7", "3.8", "3.9", "3.10"]
         os: [ubuntu-latest, macos-latest]
 
     steps:
diff --git a/CHANGELOG b/CHANGELOG
index 1394619cb..fb38ff58e 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -5,6 +5,7 @@
 ## [0.40.0] UNRELEASED
 ### Changes
 - Moved 'pytree' parsing tools into its own subdirectory.
+- Add support for Python 3.10.
 
 ## [0.32.0] 2021-12-26
 ### Added
diff --git a/setup.py b/setup.py
index 70e57da68..8b00835ab 100644
--- a/setup.py
+++ b/setup.py
@@ -61,6 +61,10 @@ def run(self):
           'Programming Language :: Python :: 2.7',
           'Programming Language :: Python :: 3',
           'Programming Language :: Python :: 3.6',
+          'Programming Language :: Python :: 3.7',
+          'Programming Language :: Python :: 3.8',
+          'Programming Language :: Python :: 3.9',
+          'Programming Language :: Python :: 3.10',
           'Topic :: Software Development :: Libraries :: Python Modules',
           'Topic :: Software Development :: Quality Assurance',
       ],
diff --git a/tox.ini b/tox.ini
index f42b884f0..5134916dc 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist=py27,py34,py35,py36,py37,py38
+envlist=py27,py36,py37,py38,py39,py310
 
 [testenv]
 commands=
diff --git a/yapf/yapflib/yapf_api.py b/yapf/yapflib/yapf_api.py
index 804c9d547..3912e0135 100644
--- a/yapf/yapflib/yapf_api.py
+++ b/yapf/yapflib/yapf_api.py
@@ -198,12 +198,12 @@ def FormatCode(unformatted_source,
 
 
 def _CheckPythonVersion():  # pragma: no cover
-  errmsg = 'yapf is only supported for Python 2.7 or 3.4+'
+  errmsg = 'yapf is only supported for Python 2.7 or 3.6+'
   if sys.version_info[0] == 2:
     if sys.version_info[1] < 7:
       raise RuntimeError(errmsg)
   elif sys.version_info[0] == 3:
-    if sys.version_info[1] < 4:
+    if sys.version_info[1] < 6:
       raise RuntimeError(errmsg)