diff --git a/pyproject.toml b/pyproject.toml
index fda9f4b6..7f54b3d3 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "rhoknp"
-version = "0.3.0"
+version = "0.3.1"
 description = "Yet another Python binding for Juman++/KNP"
 authors = ["Hirokazu Kiyomaru <h.kiyomaru@gmail.com>", "Nobuhiro Ueda <ueda@nlp.ist.i.kyoto-u.ac.jp>"]
 repository = "https://github.com/ku-nlp/rhoknp"