John Cronin may refer to:
- John Cronin (horticulturist), director of the Royal Botanic Gardens, Melbourne
- John Cronin (New Zealand), politician, currently the chairperson of the Bay of Plenty's regional council
- John Desmond Cronin, British politician
- John Cronin (convict), repeat-offense Scottish convict who become the first convict to be tracked by satellite in the UK
- John Francis Cronin, priest, author of Communism: a World Menace