A method of intercorporate information-sharing between a product-manufacturing company and a product-inspecting company includes transmitting product quality and manufacturing number information from a product-manufacturing company's database storage device to a product-inspecting company's database storage device, inspecting a product, manufactured by the product-manufacturing company, by the product-inspecting company and storing an inspected result information of the product in the product-inspecting company's database storage device and transmitting the inspected result information from the product-inspecting company's database storage device to the product-manufacturing company's database storage device.