diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index a5e1c50..6089479 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -10,7 +10,7 @@ jobs:
     strategy:
       matrix:
         os: ["ubuntu-latest", "windows-latest", "macos-latest"]
-        py: ["3.13-dev", "3.12", "3.11", "3.10", "3.9", "3.8"]
+        py: ["3.14-dev", "3.13", "3.12", "3.11", "3.10", "3.9"]
 
     runs-on: ${{ matrix.os }}
     name: Run test with Python ${{ matrix.py }} on ${{ matrix.os }}
diff --git a/pyproject.toml b/pyproject.toml
index d93e15c..50597e6 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,5 @@
 [build-system]
-# 75.3.0 is the latest version supporting Python 3.8
-requires = ["setuptools >= 75.3.0"]
+requires = ["setuptools >= v80.9.0"]
 build-backend = "setuptools.build_meta"
 
 [project]
@@ -11,13 +10,12 @@ authors = [{name="Inada Naoki", email="songofacandy@gmail.com"}]
 description = "MessagePack serializer"
 readme = "README.md"
 keywords = ["msgpack", "messagepack", "serializer", "serialization", "binary"]
-requires-python = ">=3.8"
+requires-python = ">=3.9"
 classifiers = [
     "Development Status :: 5 - Production/Stable",
     "Operating System :: OS Independent",
     "Programming Language :: Python",
     "Programming Language :: Python :: 3",
-    "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
@@ -45,7 +43,7 @@ version = {attr = "msgpack.__version__"}
 
 [tool.ruff]
 line-length = 100
-target-version = "py38"
+target-version = "py39"
 lint.select = [
     "E", # pycodestyle
     "F", # Pyflakes