Maria del Mar del Castillo () is a Canadian television actress.
Maria del Mar played in recurring roles on series like Street Legal, TekWar, Mercy Point, Relativity, Blue Murder, Terminal City and Murdoch Mysteries.
She was married to screenwriter Guy Mullally, who met on the set of Street Legal. The marriage had two children, a girl named Paloma and a boy named Gabriel.
Her performance in A Touch of Grey (2009) earned her a Canadian Comedy Award in the 13th ceremony for the best female performance in a feature and nominated in 2001 to Gemini Award in the 16th edition for best performance by an actress in a continuing leading dramatic role for Blue Murder.