Kyle Kuzma and Winnie Harlow have taken their relationship to the next level -- they got engaged!!!

The Milwaukee Bucks forward proposed to the model in a romantic way ... revealing he popped the question with a poem while they were flying to Turks and Caicos for an All-Star Break getaway on February 13.

Harlow, 30, told VOGUE the last line of Kuz's poem read, "Will you be my wife?" ... and she, of course, accepted!!

After the engagement, Harlow's family surprised her at the villa with "Let's Get Married" by Jagged Edge playing in the background ... and her reaction was priceless.

The couple shared the exciting news on Tuesday with Instagram photos ... including Harlow's 8.5-carat oval-cut engagement ring that features two baguette stones.

Kuz, 29, designed the ring himself ... claiming he spent three months making sure it was "elegant, but very timeless and simplistic at the same time."

Kuzma -- who won a championship with the Lakers -- and Harlow have been dating since 2020 ... and aside from a brief breakup, they've been inseparable ever since.