Gabrielle Union Turns Up the Heat in Cheeky Red Bikini

Gabrielle Union might be on vacation, but her body never takes a day off ... just look at these smokin' hot pics of the enchanting actress on a Miami beach.

The star took her talents -- and her seemingly endless legs -- down to South Beach over the weekend ... where she enjoyed the sun, surf and sand with her Hall of Fame husband, Dwyane Wade.

Gabrielle stunned in a bright red two-piece that left to the imagination ... showing off nearly every inch of bodacious bod.

She wore a bandana over the luscious locks ... and alternated between dipping into the ocean blue and heading back up to dry land for some much-needed rays.

Unclear if this is a birthday trip for the star ... though the seemingly ageless actress turns 54 on Thursday -- so this could be a pre-bday celebration.

While Dwyane played a majority of his fantastic NBA career in Miami, he and Gabrielle reportedly are living in Los Angeles these days ... and L.A. is where Gabrielle recently made a splash -- when she reunited with her "10 Things I Hate About You" co-stars during Julia Stiles' tribute to Heath Ledger on "Dancing with the Stars."

The cast reunion took fans by surprise ... and, just like Gabrielle, every one of the stars is aging like fine wine -- emphasis on fine!