Aiming at the deficiency of the existing radar system effectiveness evaluation methods, an effectiveness evaluation method based on AHP-extension cloud model is proposed to complete the effectiveness evaluation of different modes of single-band and multi-band radar systems and the comprehensive evaluation of single-type radar. The evaluation results show that the effectiveness of multi-band radar in the same mode is higher than that of single-band radar, and the physical characteristics of multi-band radar are lower than that of single-band radar in the comprehensive evaluation. The results show that the method has good discrimination and effectiveness for the quantitative evaluation of the system, and provides reference suggestions for the development of radar and other systems.