The Pope will for the first time allow women to vote at an influential global meeting of bishops in October, a move that has been welcomed as historic.
The new rules will give five religious sisters voting rights at the synod, which is a papal advisory body.
In the past, women were only allowed to attend the gathering as observers.
Men will still cast the majority of votes at the influential gathering.
The reforms are seen as a significant shift for the Roman Catholic Church, which has been male-dominated for centuries.