Abstract: This study focuses on the detonation performance and equation of state (EoS) of a low-density composite explosive mixed in a certain proportion of PBX-9502 powder and 502 glue. The theoretical analysis method is used based on the BKW program. The main work includes calculating the heat of formation of Kel-F (PBX-9502 binder) and ethyl cyanoacrylate (main component of 502 glue) using the group contribution method, determining the standard entropy temperature coefficient and excess volume of 18 product gases containing F and Cl elements, and calculating the CJ detonation velocity and pressure of the products for five ratios and four density states under the framework of the BKW program. The corresponding JWL EoS parameters are fitted based on the calculated CJ isentropic line. The results show that the detonation velocity and pressure are positively correlated with initial density, but negatively correlated with the content of 502 glue. The relevant results provide a theoretical basis for the selection of 502 glue ratio and mixed charge density in practical applications. The obtained JWL EoS parameters can also be used by general detonation calculation software to evaluate the detonation performance of devices. The relevant method can also be directly extended to the study of detonation parameters of other formulated explosives (sulfur, aluminum), which has important engineering application value。