John Callahan

John Callahan may refer to:


 * John Callahan (actor) (1953–2020), American actor; best known from the soap opera All My Children
 * John Callahan (cartoonist) (1951–2010), cartoonist
 * John Callahan's Quads!, a 2001 animated television series


 * John Callahan (Wisconsin politician) (1865–1956), Wisconsin Superintendent of Public Instruction
 * John B. Callahan (born 1969), mayor of Bethlehem, Pennsylvania and Democratic nominee for the U.S. House of Representatives
 * John F. Callahan, writer and editor of numerous volumes related to African-American literature
 * John H. Callahan (1845–1914), American Civil War soldier and Medal of Honor recipient
 * John M. Callahan, chairman of the Democratic Party of Wisconsin
 * John Ross Callahan (1853–1918), American dentist
 * John Callahan (catcher) (1878–1952), American baseball player
 * John Callahan (pitcher) (1874–1954), baseball player
 * John Callahan (skier) (born 1962), American Olympic skier
 * John Callahan (wrestler) (born 1964), American professional wrestler
 * John Callahan (outlaw) (1866–1936), American outlaw and bank robber