diff --git a/src/mo_basis/EZFIO.cfg b/src/mo_basis/EZFIO.cfg
index 4c4f1eca..8349c006 100644
--- a/src/mo_basis/EZFIO.cfg
+++ b/src/mo_basis/EZFIO.cfg
@@ -32,6 +32,12 @@ doc: |MO| occupation numbers
 interface: ezfio
 size: (mo_basis.mo_num)
 
+[mo_symmetry]
+type: integer
+doc: MOs with the same integer belong to the same irrep.
+interface: ezfio
+size: (mo_basis.mo_num)
+
 [mo_class]
 type: MO_class
 doc: [ Core | Inactive | Active | Virtual | Deleted ], as defined by :ref:`qp_set_mo_class`