diff --git a/pyproject.toml b/pyproject.toml
index 60e15ea85481d72b2721ad049de09748798dcee6..9075982aad00d3a19e39155fbc2c3109aa1e7290 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -38,5 +38,5 @@ pyaes = "^1.6.1"
 black = { version = "^19.3b0", python = "^3.6" }
 mypy = "^0.730"
 pylint = "^2.4.2"
-sphinx = "^2.3.1"
+sphinx = "^3.0.2"
 sphinx_rtd_theme = "^0.4.3"