To eliminate the damage of a card base material even if an external force is applied to a card by providing one or more holes at a core in the card having a memory medium held in a non-contact state by sealing the core covering the entire memory medium connected with a coil with resin in the base material.

The entire memory medium connected with a coil 4 to an IC 3 is covered with rain, sealed and a core 1 is molded. Then, at least one or more holes 2 are opened at the core 1. The holes 2 are so provided as to be uniformly dispersed on the surface of the core 1 at about 1/2 or more of the area of the core 1. Then, the core 1 is installed in a mold, and thermoplastic resin is cast to form a card. Films made of the thermoplastic resin are laminated to both sides of the core 1 to complete a predetermined card. Thus, according to that the two or more holes 2 are provided at the core 1, even if the card is unnaturally bent, the force is dispersed by the holes 2 to make it possible to prevent the damage of the card.