Barnes, who was not present in court, entered his plea Tuesday through his attorney.
Superior Court Judge Burt Pines sentenced him to two years of probation. The judge also ordered Barnes to complete 30 hours of community service and attend 13 counseling sessions with a private therapist.
Authorities say Barnes, 32, resisted arrest when a Manhattan Beach police officer attempted to take him into custody in July on an outstanding warrant for driving with a suspended license.
In court Tuesday, his attorney provided proof that he has obtained a valid license.
Barnes, who played the previous two seasons with the Los Angeles Lakers, recently signed with the Clippers for next season.