Nigerians may be Muslim, Christian or members of a traditional religion. The northern and western areas are predominantly Muslim and the southern districts are predominantly Christian.

In traditional religious systems, people believe in a supreme being who rules the universe, and in supporting deities, spirits and ancestors who act as intermediaries between the supreme being and humans. Offerings are made to please the supreme being through the intermediaries. Traditional religious practices are closely connected with traditional medicine and magical practices.

Each individual goes through a series of rites and rituals based on age and changing status. Members of one's community and traditional diviners play important roles in initiation ceremonies. Elaborate burial ceremonies accompany a death. These ceremonies vary according to the age, gender and social status of the person.

Masquerades and masks are important in traditional religion. Masquerades vary greatly from community to community. The masks represent ancestors, who visit the land of the living. Costumes are made of grass, palm fronds, cloth or raffia. Masks are made from carved wood.

 Did you know?
The Kola nut is an important symbol in the Nigerian belief system. Breaking the Kola nut is part of any welcoming ceremony. Among the Ibos, the Kola nut is broken by the youngest person present. Among the Yoruba and Edo it is broken by the oldest person. "He who brings Kola nut brings life" is a popular expression in many parts of Nigeria.

Although some masquerades have been started by women, women are usually excluded from the masquerades. Only women past childbearing age are allowed into some of the cults.

Islam spread to Nigeria from North Africa more than 1,000 years ago. Some Yorubas and almost all Hausas are Muslim. All Muslims are expected to follow the Five Pillars of Islam: making a declaration of faith (shahada), daily prayers (salat), paying the zakat tax, fasting during Ramadan (saum) and making a pilgrimage to Mecca (Hajj) at least once in a lifetime. Nigerians who have made the pilgrimage are called al-Hajj.

Christianity was introduced to Nigeria during the colonial period. Most Ibos are Christians; there are smaller numbers of Christians among other ethnic groups. Traditional religious practices such as ancestor worship, magic and sorcery are often accommodated within the practice of Christianity.

In the early 20th century the Aladura or the "praying" churches came into existence in Nigeria. Examples of Aladura churches are the Christ Apostolic Church and the Cherubim and Seraphim. Aladura churches stress the importance of visions and prayers and reject medicine as a cure for illness..