Mergenthaler is a German surname. Notable people with the surname include:
Christian Mergenthaler (1884–1980), Nazi German politician and Ministerpräsident of Württemberg Ottmar Mergenthaler (1854–1899), German-American inventor of the Linotype machine Sara Mergenthaler (born 1979), American sports sailor
See also Mergenthaler Linotype Company, a US corporation founded in 1886 to market the Linotype machine Mergenthaler Vocational-Technical High School, a trade school in Baltimore, Maryland Morgenthaler (name) Morgentaler