Juvenile's been busted in his hometown for failing to pay his baby mama $150,000 in child support ... and he's not going anywhere soon unless he forks over the money.
The 42-year-old rapper is behind bars in a New Orleans where the judge gave him an ultimatum ... pay the dough or spend 30 days in the slammer.
Seems Juvenile is grossly behind on payments owed to Dionne Williams, with whom he has a teenage son.
For now authorities have backed that azz up ... in jail.