James Leonard Gaynor (born 1944) is an Irish former hurler who played as a left wing-back at senior level for the Tipperary county team.
Gaynor captained St Flannan's to the Dean Ryan Cup title in 1961 after a 6–07 to 1–03 defeat of De La Salle College Waterford in the final.
He enjoyed his first major success in 1959 when he captained Kilruane to the Tipperary U15HC title after a defeat of a Babs Keating-inspired Ballybacon-Grange in the final.
Gaynor made his first appearance for the Kilruane MacDonaghs senior team in a tournament game against Thurles Sarsfields on Easter Sunday 1962.
Gaynor claimed his first senior silverware in 1965 when Kilruane beat Lorrha to win the North Tipperary SHC, however, success at county level had eluded the club.
Gaynor brought his 34-year playing career to an end when he lined out in goal in a North Tipperary JBHC game against Moneygall in 1989.
He won a Munster MHC title that year after lining out at centre-forward in the 10-point defeat of Cork, however, Tipperary were beaten by Kilkenny in the 1962 All-Ireland minor final.