A polyamide resin composition for microcellular foaming injection molding relates to a polyamide resin composition including a polyamide resin, a glass fiber, a mineral, and sulfonamide-based or dicarboxylic acid-based plasticizer. The resin enables a decrease in the weight of the manufactured goods and improved surface properties without showing any defect, such as surface sink and flowmark, or any reinforcing materials, such as glass fiber and clay, on the surface, while elevating other physical properties such as heat resistance, fluidity, and rigidity.