The invention discloses a multi-layer composite non-woven fabric processing method, comprising a processing device, a fabric feeding mechanism, a fabric feeding opening, a first wheel frame, first limiting wheels, a fabric feeding roller, a hot pressing mechanism, a bottom plate, support legs, a hot pressing bin, brackets, a hot press table, steam guide holes, a steam generator, a water supply pipe, a mounting frame, hot press rollers, a steam pipe, steam nozzles, ventilation holes, a circulation mechanism, an exhaust hood, an exhaust pipe, an exhaust machine, a steam guide pipe, branch pipes,a cloth discharge mechanism, a cloth outlet, a second wheel frame and second limiting wheels. A technical problem solved by the multi-layer composite non-woven fabric processing method is to overcomethe defects of low processing efficiency and poor effect of multi-layer non-woven fabric at the prior art. The multi-layer composite non-woven fabric processing method has the characteristics of simple operation, high processing efficiency, good effect, and energy conservation.