BEIJING—A low-budget, domestically produced comedy has unexpectedly become the highest-grossing Chinese film to date.

Chinese state media say the wacky road movie "Lost in Thailand" has grossed more than 1 billion yuan ($160 million) since its Dec. 12 debut. The official Xinhua News Agency, citing an independent monitor of box office figures, said Wednesday that it also beat James Cameron's "Titanic" in 3-D, the most popular foreign film in 2012, in Chinese theaters.

Set in Thailand, the film tells the story of two businessmen who go searching for their boss in the north, and then link up with a tourist eager to explore the country. It is filled with slapstick humor and action scenes.

The previous record for a domestic film was 726 million yuan set by "Painted Skin 2."