Louis Christian Mullgardt (1866-1942) was an American architect associated with the First Bay Tradition. He designed houses in Berkeley, Oakland and other cities; the Court of the Ages at the 1915 Panama–Pacific International Exposition; the San Francisco Juvenile Court and Detention Home; the Durant School in Oakland; and a major renovation of the former M. H. de Young Memorial Museum. He married Laura R. Steffens in Chicago on June 9, 1897, and they had two children. He died in San Francisco on January 12, 1942.