diff --git a/tools/ci/gha-install.sh b/tools/ci/gha-install.sh
index fb81fcea2d1..2cef974d346 100755
--- a/tools/ci/gha-install.sh
+++ b/tools/ci/gha-install.sh
@@ -40,7 +40,7 @@ if [[ $MPI == 'y' ]]; then
     export CC=mpicc
     export HDF5_MPI=ON
     export HDF5_DIR=/usr/lib/x86_64-linux-gnu/hdf5/mpich
-    pip install wheel cython
+    pip install wheel "cython<3.0"
     pip install --no-binary=h5py --no-build-isolation h5py
 fi