Night at the Museum: Battle of the Smithsonian is a 2009 American fantasy comedy film written by Robert Ben Garant and Thomas Lennon, produced by Chris Columbus, Michael Barnathan and Shawn Levy and directed by Levy. The film stars Ben Stiller, with Ricky Gervais, Amy Adams, Owen Wilson, Steve Coogan, Hank Azaria, Christopher Guest, Alain Chabat, Jon Bernthal, Rami Malek and Robin Williams. It is the second installment in the Night at the Museum series, following Night at the Museum (2006).

The film was theatrically released on May 22, 2009, by 20th Century Fox. Like its predecessor, it received mixed reviews and became a box-office success, grossing $413 million on a $150 million budget. A live-action sequel Night at the Museum: Secret of the Tomb was released on December 19, 2014, and an animated sequel, Night at the Museum: Kahmunrah Rises Again, was released on the streaming service Disney+ in 2022.