The 1904 St. Louis Jain temple is a historic structure that was constructed for the 1904 St. Louis World's fairs, termed "Louisiana Purchase Exposition". It was the first building in the United States designated as a Jain temple, since it was a temple in India, although there were no Jains in the United States at that time. It later stood in Las Vegas where some members of the Los Angeles Jain community discovered it in 1980. It now stands within the Jain Center of Southern California in Los Angeles.

The Louisiana Purchase Exposition, informally known as the St. Louis World's Fair, was an international exposition held in St. Louis, Missouri, United States, from April 30 to December 1, 1904. Local, state, and federal funds totaling $15 million were used to finance the event. More than 60 countries and 43 of the then-45 American states maintained exhibition spaces at the fair, which was attended by nearly 19.7 million people.