In order to study accompanying jamming ability of space-based laser against high orbit satellite,the theoretical model of space-based laser interference was established.Firstly,the characteristics of accompanying laser interference were analyzed,and the characteristics of laser transmition system,tracking and pointing accuracy,receiving optical system and the detector itself were analyzed respectively.Based on the analysis,the mathematical model of the received laser power density was established,and the maximum interference distance was used to evaluate the interference efficiency.The analysis shows that the efficiency of laser jamming is related to the laser power,divergence angle,laser wavelength,interference threshold and so on.Finally,taking the scanning detector of SBIRS as an example,the interference efficiency of space-based laser was quantitatively analyzed.