69 was behind bars in New York after NYPD hooked him up over a misdemeanor battery charge for allegedly roughing up a kid in Harris County, Texas.

He was taken to Rikers where he was awaiting extradition, but the judge allowed him to post $150k bail with the promise he'd fly back to Harris County and surrender himself.

Tekashi was true to his word, flying to TX over the weekend and showing up just after midnight Monday with his attorney Carl Moore where he surrendered, posted $5k bail and walked out. The rapper was dressed in a white dress shirt and pink tie.

His arraignment is set for Friday but we're hearing he may be in court Monday morning ... it's unclear why he'd have to show up before the arraignment.

The misdemeanor carries a maximum of 1 year in jail.