The Las Vegas Review-Journal reports the 33-year-old was ruled guilty Tuesday of misdemeanor domestic violence battery and assault. A felony charge was dropped as part of a plea deal.
Johnson was sentenced to one year of probation and ordered to pay a $345 fine. He must also perform 48 hours of community service and attend six months of counseling.
Police arrested Johnson Oct. 5 at a Bellagio hotel room amid allegations that he beat and strangled his ex-girlfriend.
Johnson starred for the Kansas City Chiefs, but most recently played for the Miami Dolphins in 2011.
He was arrested several times during his nine-year NFL career.
Source: Associated Press