John Cox was born in Darvel, Scotland in 1911. He played for Hamilton Academicals in the Scottish League. In seasons 1934-35, 1935-36 and 1936-37, Cox helped his club finish in the top half of the Scottish First Division table.

Cox joined Preston North End in 1938. A left-half he was signed to provide cover for Bill Shankly and Jimmy Milne. He scored a goal in his second game but that season he only played in five games.

Cox was disillusioned with his stay in the Football League and on the outbreak of the Second World War he returned to Scotland.

It is not known what happened to John Cox after this date.