In order to clarify the structure-activity relationship between the microscopic pore structure of zeolites and the reaction performance of polyethylene, the performance of four zeolites with different pore structures (regular microporous channels and cage structures) in the catalytic cracking reaction of polyethylene were explored. It is found that for SAPO-34, the long chain hydrocarbons produced by the initial thermal cracking are difficult to enter the pores of the zeolite for catalytic cracking, and the products are mainly long chain alkanes/olefins. Thermal cracking intermediates are more likely to be catalytically cracked into light olefins in the pores of ZSM-5 zeolites. The large pores of Beta and USY zeolites provide a certain space for the secondary reactions of low carbon olefins (such as Diels-Alder reaction, cyclization and aromatization), and the final products contain more aromatic hydrocarbons. Compared with Beta zeolite, the unique cage structure of USY limits the contact and further reaction of the reaction intermediates with some active sites to a certain extent, and reduces the yield of aromatics and light olefins.