The invention discloses a direct-penetration microwave heating curing method for a multidirectional carbon fiber reinforced composite material. The direct-penetration microwave heating curing method is characterized in that perpendicular-penetration microwaves are stimulated inside a part made of the multidirectional carbon fiber reinforced composite material for directly heating and curing the part. In order to solve the problem that a multidirectional laminating carbon fiber reinforced composite material cannot be subjected to microwave heating and curing, the invention discloses a method for directly heating the multidirectional laminating carbon fiber reinforced composite material through perpendicular-penetration microwaves (microwaves with electric fields in a part normal direction and a transmission direction inside the part). A metal grating is placed on the surface of the part made of the multidirectional carbon fiber reinforced composite material. Microwaves in a resonant cavity stimulate perpendicular-penetration microwaves inside the part made of the composite material under action of the metal grating, so that the multidirectional carbon fiber reinforced resin based composite material is directly penetrated, and therefore, part curing is completed. The direct-penetration microwave heating curing method solves the problem that the multidirectional carbon fiber composite material cannot be subjected to microwave heating, so that theoretical basis and technical support are provided for industrial application of the microwave heating curing technology of the composite material.