(Arranged chronologically, principals marked with asterisks)
*Ezra M. Bagley 1881-1886 principal
Benjamin Bowron 1881-1885; 1886-1887
*Richard Shuebruk 1885-1887 (1886-1887 principal)
*Edward N. Lafricain 1887-1893 principal; 1896-1897; 1900-1902
*Pierre Mueller 1888-1900 (1893-1900 principal)
Joseph F. Mann 1891-1937
*Louis Kloepfel 1898-1927 (1900-1914 principal)
Harold E. Brenton 1902-1907
Carl E. Merrill 1904-1914
*Gustav F. Heim 1906-1920 (1914-1920 principal)
Vincent Bach 1914-1915
Giovanni Nappi 1915-1919
A. Kearney 1920-1921
Gustav Perret 1920-1933
*Georges Mager 1919-1950 (1920-1950 principal)
Otto Kurt Schmeisser 1923-1926
Jean Marcel La Fosse 1926-1927; 1928-1958
O. Herman Jones 1927-1928
René Voisin 1927-1952
Alvin Howard Ball 1937-1942
Théodore Grundey 1930-1935
*Roger L. Voisin 1935-1943; 1945-1973 (1950-1965 principal)
Harry Herforth 1946-1951
*Armando Ghitalla 1951-1979 (1965-1979 principal)
Gerard Goguen 1952-1978
André Côme 1957-1987
*Rolf Smedvig 1973-1981 (1980-1981 principal)
Timothy Morrison 1978-1984; 1987-1998
*Charles Schlueter 1981-2006 principal
Charles Daval 1983-1987
Peter Chapman 1984-2008
Steven Emery 1988-1991
*Thomas Rolfs 1991-present (became principal in 2006)
Benjamin Wright 2002-present
Thomas Siders 2010-present
Michael Martin 2010-present