BTT(bank-to-turn) missiles have overwhelming advantages than STT(skid-to-turn) missiles in aerodynamic efficiency, maneuverability, controllability, and the like. However, traditional methods of guidance law designing for BTT missiles face many challenges due to its motion coupling characteristic. In this paper the researches in BTT missile guidance law designing were surveyed. In detail, the basic problem for BTT missile guidance was described firstly, and the difficulties in guidance law designing were analyzed, that is, the factors such as motion coupling, multi-constraints, target maneuver, dynamic effects of missile body, and so on, should be considered synthetically. Then the state of the art in BTT missile guidance law designing was discussed, which could be classified as channels decoupling method, sphere coordinate method and modern geometry method. Finally the further directions of BTT missile guidance law were proposed.