Alfred John Day Diver (born 6 July 1823 in Cambridge; died 25 March 1876 in Rugby) was an English cricketer whose career spanned the 1843 season to the 1866 season. Diver played mainly for Cambridgeshire CCC during its period as a first-class county and also played for Middlesex and Nottinghamshire CCC.
Popularly known as "Ducky", Diver is best known as a reliable batsman for various All-England Eleven teams. Following the 1859 English cricket season, he was one of the 12-strong party of English players who toured North America. Led by George Parr, this was the first ever overseas cricket tour.
His nephew, Edwin Diver, played over 200 first-class games, mostly for Surrey CCC and Warwickshire CCC.