Fatty and Mabel at the San Diego Exposition is a 1915 American silent black-and-white short comedy film, directed by Fatty Arbuckle and starring Arbuckle and Mabel Normand.

Fatty gets in trouble by flirting with a passing woman (Minta Durfee) while Mabel shops.

He is accosted by both Mabel and the woman's husband; eventually the police are called to straighten the whole thing out.

Arbuckle and Normand followed the Keystone tradition of showing up at an actual event and using that as background for a largely improvised film.

The event in this case was the Panama–California Exposition, held in Balboa Park in San Diego, California, in 1915–1916.