King Tom (1851–1878) was a British Thoroughbred racehorse and a leading sire in Great Britain & Ireland.

He was a bay horse foaled in 1851, sired by Harkaway and out of the exceptional mare Pocahontas by Glencoe.

King Tom was a half-brother to 14 of Pocahontas' foals including, Auricula (a stakes winner), plus Stockwell and his brother, Rataplan, both being by The Baron.

[2] King Tom is the damsire of Favonius, winner of the 1871 Epsom Derby and the grandsire of the Irish Derby winner Umpire plus the grandsire of United States Racing Hall of Fame inductee, Ten Broeck.

He was buried in the grounds of Mentmore Towers beneath a life sized bronze statue by Sir Joseph Boehm.