• John Rees (activist), British political activist (RESPECT/Socialist Workers' Party)
• John Rees (journalist), American journalist
• John Rees (rugby player), Welsh rugby union international
• John David Rees (1854–1922), colonial administrator in British India and Member of Parliament
• John Milsom Rees (1866–1952), Welsh surgeon
• John Rawlings Rees, British psychiatrist

See also

• Jonny Rees, Mr. Wales 2008
• John Rees-Jones (born 1948), British jazz double bass player and teacher
• John Reese (disambiguation)
• John Rhys, scholar
• John Rhys-Davies, Welsh actor