The Marapu religion (also known as Marafu in Sumbawa) is a form of ancestral religion that is practised mainly in the island of Sumba. Marapu is also practised in many more remote areas of Sumbawa and Flores. Both the Christains and Muslims on these islands tend to combine these two faiths together.

They believe in temporary life in the world and the eternal life in the Doomsday, in the world of spirits in Marapu heaven - Prai Marapu The world Marapu means firstly, the occupants of the eternal heaven, who lead a similar existence to men. They live in couples and one of these couples is the ancestor of the Sumbanese. Secondly, the spirits of Sumbanese ancestors in Prai Marupu. Thirdly the spirits of their relatives, and fourthly, all spirits dwelling the universe. Marapu has mysterious and magical authority over human life.

Any spirits, according to Marapu beliefs, consist of two elements i.e. Ndewa and Hamanangu. In short, the Marapu concepts are the teachings about the balance of the universal life through which the happiness can be gained. The balance is symbolized by the Great Mother (ina Kalada) and the Great Father (Ama Kalada). who live in the universe and take the forms of the moon and the sun. In mythology, they are husband and wife who gave birth to the ancestors of the Sumbanese.

The honor Marapu, the Sumbanese put effigies, called Marapu statues, on stone altars where they lay their offerings in the forms of Sirih Pinang (a dish containing betel leaves, nuts and lime) and sacrificial cattle. The statues of Marapu are made of wood in the shape of human faces. These images are usually placed in the yard of their houses or inside the traditional houses.