Latin legend Stevie B just pled guilty to owing $420,000 in unpaid child support -- but he has promised the court ... he's gonna do his damnedest to pay it off.
Stevie -- real name Steven Bernard Hill -- was arrested outside his concert in Massachusetts this weekend for owing the enormous sum to his baby mama.
Stevie was arraigned in court this morning -- and according to court sources, he promised to pay $921.25 a week in child support, and an additional $500 a month toward his arrears.
Stevie B is still in custody -- and must pay a $10,000 lump sum toward the $420,000 balance in order to get out of jail.
Stevie's lawyer tells TMZ, "This was an unfortunate misunderstanding and Stevie B is a wonderful and loving father and caring husband." He's due back in court on November 18th.