diff --git a/.ci_support/environment-openmpi.yml b/.ci_support/environment-openmpi.yml
index e58d7df8..d9a7fd12 100644
--- a/.ci_support/environment-openmpi.yml
+++ b/.ci_support/environment-openmpi.yml
@@ -3,7 +3,7 @@ channels:
 dependencies:
 - python
 - numpy
-- openmpi
+- openmpi =5.0.5
 - cloudpickle =3.1.0
 - mpi4py =4.0.1
 - pyzmq =26.2.0