diff --git a/pyproject.toml b/pyproject.toml
index c68b8c200..fbb3e6717 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,3 +1,3 @@
 [build-system]
-requires = ["setuptools >= 51.0.0", "wheel"]
+requires = ["setuptools >= 51.0.0", "wheel", "numpy<2.0.0"]
 build-backend = "setuptools.build_meta:__legacy__"