The couple, who appeared together this summer in the live-action film version of the cartoon "Scooby-Doo," got married Sunday at an undisclosed location in Mexico, according to their spokeswoman.
The bride wore a Vera Wang gown and the groom wore a custom-made linen suit, said spokeswoman Leslie Sloan. Friends and family attended the ceremony, which was kept a closely guarded secret from the public.
US Weekly says about 60 people attended, including Shannen Doherty and Dule Hill from "The West Wing." The choreographer for "The Wedding Planner" and many other movies, Adam Shankman, performed the ceremony. The wedding was originally planned for outdoors, but it rained.
Gellar, star of the UPN series "Buffy the Vampire Slayer," announced the engagement at her 24th birthday party in April 2001.
The couple met on the set of the 1997 teen slasher flick, "I Know What You Did Last Summer." They dated for nearly a year before getting engaged.
Both are signed to star in a sequel to the "Scooby-Doo" adaptation, in which Prinze, 26, played brawny, mystery-solver Fred and Gellar portrayed sweetheart sleuth Daphne.