Daniel Refoua sued Stewart over a fight at a nightclub in 2006 he says left him with a broken nose and other injuries.
The case had been scheduled to go to trial in January, although Stewart's attorneys had been seeking a dismissal. An attorney for Stewart did not return a phone message Thursday.
Stewart appeared in the A&E show "Sons of Hollywood" and is also one of the patients featured on this season's "Celebrity Rehab with Dr. Drew" on VH1.