The belief of supernatural being is the basic feature of Taoism. Taoism deems that common people may live forever and become supernatural beings as long as they can cultivate in earnest. After becoming supernatural beings, they can select to stay on the earth or live in the heaven. The supernatural being is preterhuman and has various magic powers.

When comparing supernatural beings in Taoism with the similar kind in other areas in the western world, one may easily think of deities in ancient Greek myths, because there are many similar features between them.

The names and titles of Taoist supernatural beings are numerous, so are the figures. Most of Taoist supernatural beings in Taoism were the real historical figures. According to the Taoist explanation, these immortals can be divided into three types: heaven immortals, earth immortals and immortals after death. Heaven immortals are supernatural beings that can directly go to the heaven; and earth immortals are medium-grade immortals that can only stay on the earth but can become supernatural beings when alive; and immortals after death are those people who can become supernatural beings only after they are dead. Many people have been recognized as the supernatural beings after their death even if they do not believe in Taoism when they are alive, because of their lofty morality, outstanding achievements or honorable statuses.

It is interesting that the immortal system of Taoism is a whole copy of that of the human society. In the world of supernatural beings, there is a bureaucratic system, and every immortal has his/her own official position. In this way, Taoism uses a lot of stories of supernatural beings to promote the authenticity of the kingdom of supernatural beings, and tries to prove its correctness theoretically.