PURPOSE: To produce a product of metal base reinforced material having complicate shape in high quality by preheating a preformed body, dipping this into molten metal bath after degassing, pressurizing molten metal in the bath and impregnating the preformed body with the molten metal.

CONSTITUTION: The preformed body 30 is fitted to tip part of a supporting member 31 and a cover is closed and the preformed body 30 is charged in a device 20. The preformed body 30 is heated in a preheating booth 27 and by opening a second valve 23, the device 20 is evacuated to exhaust the gas contained in the preformed body 30. The preformed body 30 is descended and dipped into the molten Al 26 in the metal bath 24. By closing the second valve 23 and opening a first valve 22, argon gas is supplied into inner part of the device 20 to pressurize the molten metal 26 for the prescribed time. By this method, the molten metal 26 enters uniformly the preformed body 30. By closing the first valve 22, the performed body 30 is pulled up from the molten metal 26 and slowly cooled in the preheating booth 27.