A hukou () is a residency permit issued in the People's Republic of China which officially identifies a person as a resident of an area.

Although a valid residency permit technically requires an individual to live in the area designated on his/her permit, in practice the system has largely broken down, and there are an estimated 150 to 200 million Chinese who are living outside their officially-registered areas. Persons without a residency permit have much less access to education and government services , and in several respects occupy a social and economic status similar to undocumented aliens in some other countries, such as the United States.

Under the command economy in the PRC before the 1980s, a residency permit was required for any employment and to receive food and other essential consumer products. After Chinese market reforms, it became possible for some to unofficially migrate and get a job without a valid permit. Economic reforms also created pressures to encourage migration from the interior to the coast as well as provided incentives for officials not to enforce migration regulations.

Reforming the residency system has been a very controversial topic within the PRC. Although the current system is widely regarded within the PRC as unfair and inhumane, the main problem with liberalization is that there are fears that it would result in a massive influx to the cities which would stress already strained government services beyond the breaking point, and result in further economic loss to rural areas.

A similar system exists within the public administration structures of the Republic of China on Taiwan.

See also

• Household registration