In an electronic components mounting process fabricating a mount circuit board due to an electronic components mounting system formed of a plurality of electronic components mounting apparatuses by connecting them to each other, data of solder paste position which is printed on the circuit board is transmitted as feedforward data to an electronic components placement apparatus and a placement state inspecting apparatus. A control parameter which controls a placing position in a components placement operation due to the electronic components placement apparatus and an inspection parameter which indicates a standard position of the components in a placement state inspection are updated on the basis of the soldering position data. Therefore, it is possible to achieve a precise mounting by effectively and properly using inspection information obtained from each process.