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.

[3] He made design proposals for multi-building complexes for downtown Honolulu in 1915 and for Yosemite Valley in 1916.

[6] Art historian Robert Judson Clark was the leading expert on Mullgardt until his death in 2011.

He wrote the catalog essay on the architect for a 1966 exhibition at the University of California, Santa Barbara and the M.H.