John Arthur Johnstone was an English footballer who made six league appearances as a forward for Port Vale in 1921 and 1922. He was the brother of fellow Vale player Harry Johnstone.
Johnstone joined Port Vale in April 1921, making his debut soon after. He played three Second Division games in both the 1920âÂÂ21 and 1921âÂÂ22 campaigns, before he was allowed to leave the Old Recreation Ground.