Mario's misdemeanour assault charges have been dropped by prosecutors.
The R&B singer and former Dancing With The Stars contestant was charged with second-degree assault for allegedly shoving his mother into a wall at their Baltimore home.
But a spokesman for the Baltimore state's attorney's office says Mario's mother, Shawntia Hardaway, changed her story on the witness stand on Tuesday.
Hardaway said she was under the influence of drugs and alcohol when she called police and that her son never laid a hand on her.
Mario's attorney, Billy Murphy, says it was clear from the beginning that his client never struck his mother and that Mario "remains committed to helping his mother battle her addiction".