The invention relates to the field of composite doors, in particular to a method for manufacturing an enhanced composite door. According to the manufacturing method, a door frame assembly and door plate assemblies are included; the door plate assemblies are suitable for being embedded into the front and rear faces of the door frame assembly, one or more locking rods are inserted from the outer side of the door frame assembly to lock the door plate assemblies, and thus the composite door is constituted. According to the method, the door plate assemblies are embedded into the door frame assemblyto constitute the composite door; and the door plate assemblies and the door frame assembly are in fastened fit through a main mounting column, an auxiliary mounting column and the locking rods, connection between the door plate assemblies and the door frame assembly is enhanced, and high-strength splicing between the door frame assembly and the door plate assemblies in the composite door is improved.