Michael J. Ryan may refer to:
Michael J. Ryan (runner) (1889–1971), winner of the 1912 Boston Marathon Michael J. Ryan (biologist) (), American biologist Michael J. Ryan (doctor) (born 1965), Irish epidemiologist, surgeon, and chief executive director of the WHO Health Emergencies Programme Michael J. Ryan (Irish politician) (died 1952), Irish barrister, professor and politician Michael J. Ryan (Philadelphia politician) (1862–1943), president of the United Irish League of America Michael James Ryan or Mike Ryan (1941–2020), American baseball player Michael Joseph Ryan (footballer) or Mike Ryan (1930–2006), English footballer Michael Joseph Ryan (media hoaxer) or Rocky Ryan (1937–2004), British media hoaxer
See also J. Michael Ryan (born 1957), American judge Michael Ryan (disambiguation) Michael Joseph Ryan (disambiguation)