Otis Keilholtz (February 8, 1838 – September 13, 1883) was an American politician. He served in the Baltimore City Council in the 1870s and served as ex-officio Mayor of Baltimore when Mayor George P. Kane was sick and after he died in office in 1878. Keilholtz served in the Maryland House of Delegates and as Speaker of the Maryland House of Delegates in 1882.