Aiming at the shortcomings of the current main reconnaissance methods satellite reconnaissance and aerial reconnaissance, a method for calculating the performance index of the low dynamic near-space platform based on the STK is proposed. The method is based on the established satellite reconnaissance performance index system, and compared the reconnaissance performance of the two typical platforms of the low dynamic near-space platform and the reconnaissance satellite by using the STK. The reconnaissance performance of the low dynamic near-space platform is analyzed quantitatively. The simulation results show that low dynamic near-space platform is effective for the tactical reconnaissance mission, realizing the continuous, real-time, fast response reconnaissance and surveillance.