The important role and major achievements of a wireless laser and radio frequency (RF) complementary communication system are introduced, and the superiority and importance of the wireless laser and RF complementary communication technologies are explained. And the basic working principle of the wireless laser and RF complementary communication system is expounded, and the feasibility of the wireless laser and RF complementary communication system is illustrated. Combining with the latest research results of the complementary communication systems in foreign countries in recent years, the key problems encountered are mainly analyzed. The challenges faced by the complementary communication systems at present are presented. The key technologies to solve these challenges are put forward. The application prospect and development trend of the complementary communication are pointed out.