With the fourth generation stealth aircraft gradually becoming the main combat equipment of major military powers in the world, the improvement of missile anti stealth combat capability has become an inevitable requirement for the construction of weapons and equipment. In the evaluation of missile operational effectiveness, real shot shooting is an essential link. At present, there are a certain number of small stealth target aircraft that can be used to simulate the main target characteristics of the fourth generation stealth aircraft. However, their analysis of simulation fidelity and the accuracy of missile operational effectiveness evaluation is rarely seen in relevant literature. This paper makes a detailed comparison and analysis of the differences between the small stealth target and the real stealth aircraft in radar scattering characteristics, physical dimensions, vulnerability, electronic countermeasure characteristics, etc. Through the study of the impact of the differences in target characteristics on missile functions and effectiveness, it is believed that the small stealth target is difficult to be comprehensive To accurately evaluate the operational effectiveness of missiles.due to its own shape and size inherent characteristics, it is necessary to attach importance to the development of large-scale stealth target aircraft, which is of positive significance for evaluating the operational effectiveness of missiles and correctly guiding the improvement of missile anti stealth capability.