Westdahl may refer to:
Ferdinand Westdahl (1843-1919), an accomplished member of the United States Coast and Geodetic survey from 1867 to 1919 John Westdahl (1916-1968), American politician SS Ferdinand Westdahl, a Liberty ship; see List of Liberty ships: A-F USC&GS Westdahl, a survey ship of the United States Coast and Geodetic Survey in commission from 1929 to 1946 Westdahl Volcano, a volcano in the Aleutian Islands