diff --git a/pyproject.toml b/pyproject.toml
index 3f52ea258f..7ff1d94c20 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -2,7 +2,7 @@
 requires = [
   "setuptools",
   "wheel",
-  "numpy==1.6.6; python_version<='3.7'",
+  "numpy==1.16.6; python_version<='3.7'",
   "numpy==1.17.5; python_version=='3.8'",
   "numpy==1.19.5; python_version=='3.9'",
   "numpy; python_version>='3.10'",