--- a/config/pmix.m4
+++ b/config/pmix.m4
@@ -1288,16 +1288,16 @@
     if test "$have_cython" = "0"; then
         AC_MSG_RESULT([yes])
         AC_MSG_CHECKING([Cython version])
-        cython_version=`python -c "from Cython.Compiler.Version import version; print(version)"`
+        cython_version=`python3 -c "from Cython.Compiler.Version import version; print(version)"`
         AC_MSG_RESULT([$cython_version])
         PMIX_SUMMARY_ADD([Required Packages], [Cython], [], [yes ($cython_version)])
     else
         AC_MSG_RESULT([no])
         # Cython doesn't have any include or lib files - it is just a binary
-        AC_CHECK_PROG(pmix_cython_rpm, cython, [cython])
+        AC_CHECK_PROG(pmix_cython_rpm, cython3, [cython])
         if test "$pmix_cython_rpm" != ""; then
             AC_MSG_CHECKING([Cython version])
-            cyvers=`cython --version 2>&1`
+            cyvers=`cython3 --version 2>&1`
             cython_version=${cyvers#"Cython version "}
             AC_MSG_RESULT([$cython_version])
             PMIX_SUMMARY_ADD([Bindings], [Cython], [], [yes ($cython_version)])