NBA's Jahlil Okafor's Dating Super Hot College Grad

Jahlil Okafor's season is already off to a GREAT start ... 'cause the 20-year-old Philadelphia 76ers superstar is dating a smoking hot bikini model ... TMZ Sports has learned.

Okafor's lady is Lauren Oglensky -- a 2014 graduate from University of Arizona where she was a "Tucson12" model (UA women who boast a 3.0 GPA or better).

Google her name ... she's fire.

Unclear how they met ... but turns out, she's from Philly, so that works out.

Sources connected to the couple tell us they've known each other for a while and are "happily together."

Congrats!