Maria del Mar del Castillo (born in 1964) is a Canadian television actress, who has starred in series such as Street Legal, Tek War, Relativity, Mercy Point, Terminal City, Blue Murder and Murdoch Mysteries.

She was born in Madrid, Spain, and grew up in Ottawa, Ontario.

She is sometimes mistakenly credited with having been the lead singer of the 1980s Canadian goth rock band National Velvet, which was in fact fronted by a different Maria del Mar.