Secret Story - Casa dos Segredos (occasionally be referred as Casa dos Segredos) is a Portuguese reality competition television show based on the original French series Secret Story, and part of the franchise of the same name. The first episode was broadcast on 3 October 2010 on TVI.

Like the original French version, although Secret Story is not a direct adaptation of the Big Brother franchise's format, created by producer John de Mol Jr. in 1997, the show has a similar concept while including his own game mechanics, and is also produced and owned by Big Brother's production company Endemol Shine Group/Banijay. The housemates are cut off from the outside world for ten to fifteen weeks in a house called "house of secrets", where every room is fitted with cameras, except the restroom. They have to keep a secret while trying to discover the other housemates' one.