A household deity is a deity or spirit that protects the home, looking after the entire household or certain key members.

The Lares and Penates of Ancient Rome are perhaps the best-known example of household gods, but many others existed. The crocodile-headed Tawaret was a popular element of ancient Egyptian mythology; she was considered to be the protector of women during pregnancy and childbirth. Bes was another popular Egyptian household god, whose duties included killing snakes, protecting children, encouraging fertility, and assisting Tawaret in childbirth.

Household deities were usually worshipped not in temples but in the home, where they would be represented by small idols (the teraphim of the Bible), amulets, paintings or reliefs. They could also be found on domestic objects, such as cosmetic articles in the case of Tawaret. The more prosperous houses might have a small shrine to the household god(s); the lararium served this purpose in the case of the Romans. The gods would be treated as members of the family and invited to join in meals, or be given offerings of food and drink.