Immigration law includes the national statutes, regulations, and legal precedents governing immigration into and deportation from a country. Strictly speaking, it is distinct from other matters such as naturalization and citizenship, although they are sometimes conflated. Countries frequently maintain laws that regulate both the rights of entry and exit as well as internal rights, such as the duration of stay, freedom of movement, and the right to participate in commerce or government.

Immigration laws vary around the world and throughout history, according to the social and political climate of the place and time, as the acceptance of immigrants sways from the widely inclusive to the deeply nationalist and isolationist. National laws regarding the immigration of citizens of that country are regulated by international law. The United Nations' International Covenant on Civil and Political Rights mandates that all countries allow entry to their own citizens.