diff --git a/requirements.txt b/requirements.txt
index d6a7aee6..03e18829 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
-numpy>=1.20.2
+numpy>=1.20.2,<2.0.0
 matplotlib>=3.3.3,<3.6.0
 rx>=3.2.0
 scipy>=1.6.0
diff --git a/setup.cfg b/setup.cfg
index 6c956f45..9f1ad091 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -20,7 +20,7 @@ package_dir=
     =src
 packages=find:
 install_requires=
-    numpy>=1.20.2
+    numpy>=1.20.2,<2.0.0
     matplotlib>=3.3.3,<3.6.0
     rx>=3.2.0
     scipy>=1.6.0