To provide a mold capable of discovering the generation of defectiveness in a cylindrical part such as a communication hole, a bottomed hole or the like and capable of abolishing an inspection process after molding and a molded article manufacturing method.

In this mold 10, a core 70 is formed into a bottomed cylindrical shape and one end of a rod-shaped detection rod 78 is fixed to the inner bottom of the core 70. The other end of the detection rod 78 is further extended to the rod housing part 82 formed in a slide core 62 from the opening end of the core 70. Moreover, a magnet 84 is fixed to the detection rod 78 in the vicinity of the other end thereof. When the core 70 is bent and the leading end of the core 70 is displaced, the detection rod 78 is revolved centering around the intermediate part in the longitudinal direction thereof accompanied by the displacement of the core and a magnetic field formed by the magnet 84 is varied. The variation of the magnetic field is detected by a magnetic sensor 86 to detect the bending of the core 70 during the molding of a resin molded article 12.