Martini-Henry (1880–1903) was a New Zealand thoroughbred racehorse who won several important races in Australia, where he was a sire of several well-known racehorses. He has been called "one of the finest ... thoroughbred[s] ever seen in Australia".
Martini-Henry's sire was Musket and from Sylvia, who was by Fisherman and from Juliet, who was by Touchstone. He was Sylvia's last foal and the first to establish Musket as the sire of great performers.
Martini-Henry was purchased by the James White for something over 1,000 guineas, at the time the highest price paid for a yearling. He did not race in 1882, but in 1883 won both the Victoria Derby and the Melbourne Cup.
In 1884 he won the VRC St Leger and came second in the AJC St Leger.
He died at the stud of E. G. Blume (c. 1861–1943) at Bexley Station, Queensland on 9 May 1903.