Derek Chadwick (born 21 March 1941) is a former Australian sportsman, playing both first-class cricket with Western Australia and Australian rules football for East Perth in the Western Australian Football League (WAFL).
Chadwick was a right-handed opening batsman who made 4082 runs at 34.30 during his cricketing career, with 9 centuries.
He toured New Zealand with the Australian team in 1969-70.
As a footballer he was a wingman and played a club record 269 games for East Perth, winning their best and fairest award twice.
In 1964 he won a Simpson Medal for his performances with the Western Australian state team in tours of Melbourne and Adelaide.