Religion of Laos is Theravada Buddhism, which is professed by most Lao and by a small number of other ethnic groups. Most of the rest of the people are animists, or spirit worshipers, especially in the more isolated upland areas. Many see no contradiction in being both, since Buddhism shows the way to enlightenment, while spirit worship helps a person to cope with daily and local problems.

Among the hill peoples, especially those who have migrated from southern China, are found groups that mix Confucian ideas with Buddhism and animism. One subgroup of the Mon-Khmer, the Lamet, practices ancestor worship, and the Hmong are both spirit and ancestor worshipers.

Roman Catholic and Protestant missionaries were present in the country before 1975, but only a tiny proportion of the population is Christian. The Vietnamese, who live both in the cities and in the northeastern rural areas, practice a mixture of Mahayana Buddhism and Confucianism.