PURPOSE: To obtain favorable external appearance and realize almost no sinking and deformation by a method wherein molten resins are injected from a plurality of injection molders, the temperature settings of which are different from one another, into a mold in the order of higher temperature.

CONSTITUTION: Injection machines 1 - 3 are normal injection machines. Nozzles are installed respectively at the tips of the injection machines 1 - 3. Further, at the tip part of the nozzles, a change-over valve 7 is installed so as to be able to selectively communicate molten resins injected from the injection machines 1 - 3 with the cavity 10 of a mold 9. The set temperatures of respective cylinders and nozzles are different from one another. When the injection machines 1, 2 and 3 are in the order named according to the height of the set temperature, firstly the injection machine 1 is injected and then the injection machine 2 and finally the injection machine 3 are injected. Thus, the molded item, which is molded as mentioned above, has a favorable external appearance and almost no sinking and deformation develops.