Bobby Brown is officially locked up ... after turning himself in to authorities moments ago.
Brown was taken into custody inside an L.A. courtroom, where he appeared with his high-powered attorney Tiffany Feder. Brown had been ordered to turn himself in following his most recent DUI conviction.
TMZ broke the story ... Brown was sentenced to 55 days in jail last month for his October arrest. It was his 3rd ever DUI conviction.
Brown also got 4 years probation stemming from the recent arrest, and he will have to complete an 18-month alcohol program.