The "Green Lantern" co-stars have been dating for about a year and recently bought a home together in Bedford, N.Y.
Their wedding reception took place in a white tent at the plantation, just outside Charleston, with Florence Welch of Florence and the Machine, performing three songs live. Other music was provided by a disc jockey, People.com said.
Lively, 25, is a cast member of TV's "Gossip Girl." She previously dated actors Penn Badgley and Leonardo DiCaprio.
Reynolds, 35, is divorced from actress Scarlett Johansson. His films include "Safe House," "X-Men Origins: Wolverine," "Definitely, Maybe" and "The Proposal."