If you do operate a boat while drunk you could lose your driver's license.
Governor Pat Quinn signed the legislation at Chicago's new 31st Street Marina.
He was joined by the family of Tony Borcia.
The 10-year-old had gone tubing with his family when he was killed last year by a drunken boater.
"The coroner told me I couldn't see his body because it was too badly damaged," said Margaret Borcia. "I told him I didn't care, that I needed to hold my son and to say goodbye to him."
The Borcia family has worked tirelessly since the incident last year to stop people from boating while intoxicated.