Recently, there has been a renewed interest in the development of battle tanks armoring, which made old generations of anti-tank missiles are no longer able to counteract modern tanks by hitting armor in the front or the side sections of the tank. Recent developments directed toward designing the antitank missiles to hit the tank from the upper ceiling which is considered one of the weakest points in the tank armor. The new generations of anti-tank missiles are developed with the ability to hit tanks from its upper section (top-attack). So, the current article focuses on developing the antitank missile guidance law to generate a top-attack trajectory considering (impact angle, missile maneuverability, miss distance) constraints. The accuracy of the generated trajectory is evaluated through two main parameters, impact angle and miss distance, a polynomial function based trajectory is proposed. Further extended analysis is carried out for evaluating missile motion parameters via a 6-DOF model. The proposed algorithm is simulated utilizing Matlab/ Simulink with different scenarios.