To easily and inexpensively produce a metal inserted resin molded article while ensuring airtightness sufficient to protect the electric circuit or contact in a part even if there is a severe environmental change.

In a method for producing a resin composite molded article having a metal part inserted therein, a needle-like or porous uniform metal fine structure is preformed to the whole or part of the surface of the metal part and this metal part is inserted in the mold of an injection molding machine to perform the injection molding of a thermoplastic resin material.