How to achieve scientific estimation for aiming error so as to improve missile system's aiming accuracy is an important content of current scientific research on shooting range measurement and test system. In this paper, against the background of a new missile weapon system's flight test, aiming error factors which affect missile hit accuracy was analyzed with the method of membership cloud gravity center interpretation, the influence degree system model of missile aiming error was established and the comprehensive evaluation was carried out. By this method, more scientific error estimation before target missile flight test is realized so as to reduce aiming errors and improve missile hit accuracy on a scientific basis.