The phenomenon of illegal immigration is one of the serious problems facing the international community as a whole. This phenomenon means the entry of person(s) to a country other than their country illegally or in an irregular way.

This phenomenon has several terms such as irregular immigration, illegal immigration, and illegitimate immigration, hidden or covert immigration. All of these terms mean, in the end, the illegality of this migration in the consideration of national and international law.

This phenomenon has evolved by the development of relations among countries, and different economic and social conditions and political conditions in the various communities, where immigration was in the early formation communities as an ordinary matter as there was no political organization called a state which impose its authorities on a certain land and regulate migration to and from it. But the development of societies and the emergence of the state in its modern concept led to the organization of this phenomenon in a legal and legitimate way among nations.

At the beginning, the industrially and commercially developed countries encouraged immigration as a result of the losses suffered in World Wars I and II and the need for urgent of labor, but gradually after these countries had no longer need to manpower and they became competing with the national manpower in these countries, they started tightening procedures to stop this phenomenon. As a reaction to these procedures and a result of a number of political, economic, security, religious, and social reasons, this phenomenon of illegal immigration has become a global problem.

This phenomenon has many negative effects on countries facing immigration from or to them (countries of origin and receiving countries). These countries which faced economic, political, security and social effects, realized the seriousness of this phenomenon and the necessity to combat it, and for this, they saved no efforts in this regard globally, regionally and nationally.

The research deals with the topic of the international efforts to combat the illegal immigration. The research is divided into two sections, the first one is dealing with the Definition of the phenomenon illegal immigration, and the second section is dealing with the efforts of combating the illegal immigration.