John May may refer to:
Business
John May (angel investor), manager of Business Angel investment groups
John May (shipwright) (1694–1779), English shipwright in Dutch service
John May (youth worker) (born 1964), chief executive of Career Academies UK and member of the World Scout Committee
John C. May, president and CEO of John Deere
Clergy
John May (bishop) (died 1598), Bishop of Carlisle
John May (priest) (died 1893), Dean of St George's Cathedral, Georgetown, Guyana
John L. May (1922–1994), Archbishop of St Louis
Politics
John May (Australian politician) (1844–1917), member of the Queensland Legislative Assembly
John May (North Carolina politician) (1950–2017), member of the North Carolina legislature
Sport
Jack May (tennis) (1925–2012), Australian tennis player
John May (Australian footballer) (born 1951), Australian footballer who played for Essendon
John May (cricketer) (1849–?), English cricketer
John May (footballer, born 1878) (1878–1933), footballer who played for Rangers FC
Other
John May (1744–1790), founder of Maysville, Kentucky
John May (gangster), car mechanic for the Moran gang, killed in the Saint Valentine's Day Massacre
John May (judge) (1923–1997), British judge who headed the May Inquiry into "Maguire Seven" miscarriage of justice
John May (Medal of Honor) (1836–1886), American soldier and Medal of Honor recipient
John May (police officer) (1775–1856), superintendent in the London Metropolitan Police
John Wilder May (1819–1883), American judge
John May (V), episode of the 2009 miniseries V