The majority of Vietnamese do not follow any organized religion, instead participating in one or more practices of folk religions, such as venerating ancestors, or praying to deities, especially during Tết and other festivals. Folk religions were founded on endemic cultural beliefs that were historically affected by Confucianism and Taoism from ancient China, as well as by various strands of Buddhism. These three teachings or tam giáo were later joined by Christianity which has become a significant presence. Vietnam is also home of two indigenous religions: syncretic Caodaism and quasi-Buddhist Hoahaoism.

Lên đồng, votive dance, "to mount the medium", or "going into trance") is a ritual practiced in Vietnamese folk religion, in which followers become spirit mediums for various kinds of spirits.