PURPOSE: To obtain a molded item colored remarkably less than expected from the content of a heat stabilizer by mixing a polyamide resin masterbatch contg. a heat stabilizer in a high content with a polyamide resin for dilution.

CONSTITUTION: A molded polyamide resin item is produced by compounding a polyamide resin with a heat stabilizer to give a polyamide resin masterbatch contg. the heat stabilizer in a high content, melt mixing and extruding the masterbatch to pelletize it, mixing the resultant master pellets with a polyamide resin for dilution so that the content of the heat stabilizer in the resultant mixture is in the range of the content required for thermal stabilization. and melt molding the mixture under necessary heating. Thus, the yellowing tendency can be restrained without detriment to the heat stability of a product by blending a masterbatch of a heat stabilizer with a resin for dilution.