Oh, buoy! Super sexy Uma Thurman takes a thrilling dip in the Mediterranean yesterday while on a cruise off Sardinia.

Uma shared the yacht with her newly minted fiancé, Swiss multimillionaire financier Arpad Busson.

“Schindler’s List” star Liam Neeson and his wife, actress Natasha Richardson, also came along for the sunny ride on the tides.

Thurman, 38, showed off her spectacular 6-foot body in a teeny-weeny white bikini as she plunged into the sea.

Her film “The Accidental Husband” opens next month.