diff --git a/conda_env.yml b/conda_env.yml
index d6c2e5c7..5b589bce 100644
--- a/conda_env.yml
+++ b/conda_env.yml
@@ -9,7 +9,7 @@ dependencies:
 - h5py
 - jupyter
 - matplotlib
-- numpy
+- numpy==1.17.4
 - pip
 - psutil
 - scipy