The invention relates to a preparation method of a non-binder ZSM-5/zeolite beta coexisting molecular sieve catalyst. In the invention, the problems that when a hydrothermal synthesis method is adopted to prepare the existing ZSM-5/zeolite beta coexisting molecular sieve, the preparation process is complicated, the cost is higher, the ZSM-5/zeolite beta coexisting molecular sieve catalyst with the binder has lower activity, the non-binder ZSM-5/zeolite beta coexisting molecular sieve has lower strength and the mechanical mixture of ZSM-5 with the binder and zeolite beta has lower activity, are mainly solved. The technical scheme in the invention comprises the following steps: mixing ZSM-5/zeolite beta coexisting molecular sieve, alkaline substance, aluminum compound and silicon oxide, forming, drying, placing the dried mixture in template agent vapor containing at least one of ammonia water, ethylenediamine, triethylamine, n-butylamine, hexanediamine, tetrapropylammonium bromide or tetrapropylammonium hydroxide, and tetraethylammonium hydroxide or tetraethylammonium bromide to perform crystallization treatment at 100-200 DEG C for 10-300 hours and obtain the non-binder ZSM-5/zeolite beta coexisting molecular sieve catalyst, wherein the weight contents of ZSM-5/Magadiite coexisting molecular sieve, alkaline substance, aluminum compound and silicon oxide calculated according to the weight of the formed and roasted catalyst are 10-80%, 0.1-10%, 0.5-20%, and 20-80% respectively. The problems can be better solved and the prepared non-binder ZSM-5/zeolite beta coexisting molecular sieve catalyst can be used in the naphtha catalytic cracking reaction for preparing propylene.