Abstract: Anti-Tactical Ballistic Missile (ATBM) operation is one of the important operational modes in future air defense. The evaluation of an ATBM system is essential for the development and deployment of relevant weapons and equipment. First, the relation between operational effectiveness and operational capability of a weapon system is analyzed. The operational capability refers to the performance of a weapon system, and is a static concept. The operational effectiveness refers to the capability of completing a mission, and is a dynamic concept. But if the operational capability includes the operational course, it is also a dynamic concept. Second, the traditional and newly developed operational capability evaluation methods are analyzed, including the advantages and disadvantages of the traditional methods. The basic idea and applications of the new methods are discussed.