Ad Valorem (foaled 27 April 2002) is an American-bred, Irish-trained Thoroughbred racehorse and sire. He was one of the leading European two-year-olds of 2004, when he was unbeaten in three races including the Middle Park Stakes. He failed to win in 2005 but returned as a four-year-old to win the Queen Anne Stakes. Since his retirement he has had some success as a sire of winners in Australia.