diff --git a/pyproject.toml b/pyproject.toml
index e2999ca..9ba1972 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -3,7 +3,7 @@ requires = [
     "wheel",
     "setuptools",
     "cython>=0.21.0",
-    "numpy>=v1.20.0",
+    "numpy>=v1.20.0, <=1.26.4",
     "scipy",
 ]
 
diff --git a/setup.py b/setup.py
index 79b894d..17632d7 100644
--- a/setup.py
+++ b/setup.py
@@ -157,7 +157,7 @@ def package_files(directory):
     package_data={"": package_data},
     ext_modules=ext_modules,
     cmdclass=cmdclass,
-    setup_requires=["numpy >= 1.20.0"],
+    setup_requires=["numpy >= 1.20.0, <=1.26.4"],
     install_requires=install_requires,
     tests_require=["nose", "coverage"],
     extras_require={