It's after several other initiatives including a free shower block, sleeping bags and haircuts.
According to Vatican Radio, the six washers and driers have been supplied by the Whirlpool Corporation.
The new laundry is located in the People of Peace Center in Rome, run by the Community of Sant'Egidio - a Christian organisation which calls itself a "a worldwide movement of lay people, based on prayer, solidarity, ecumenism, dialogue".
The cosmetics giant Proctor and Gamble is supplying the detergent for the machines.
Archbishop Konrad Krajewski, who leads the Vatican's giving to the poor, said: "Here is a concrete sign wanted by the office of Papal Charities: a place and a service to give concrete form to charity to restore dignity to so many people who are our brothers and sisters and who are called, with us, to build a city we can trust."
