John Leahy
John Leahy is the name of:
; Australia
- John Leahy (footballer), Australian rules footballer
- John Leahy (Australian politician), Australian Conservative politician, 1893–1909
- John Leahy (hurler), former Irish hurler
- John Patrick Kenneth Leahy, Irish Roman Catholic priest
- Johnny Leahy, Irish hurler
- John Leahy (Irish politician), Leader of Renua Ireland
- John Leahy (diplomat), former senior British diplomat
- John Leahy (executive), American executive at Airbus
- John E. Leahy, American politician
- John Martin Leahy, American short story writer, novelist and artist