PURPOSE: To automatically set the suitable pressurizing time and cooling time for casting with a low pressure casting machine.

CONSTITUTION: A first temp. sensor 14 for detecting molten metal temp. is arranged at a gate 6 in the low pressure casting machine and a second temp. sensor 15 for detecting sprue temp. is arranged to a lower die 2c and further, a third temp. sensor 16 is arranged to a side die 2b. Then, based on the detected values of these temp. sensors 14-16 at the time of casting, the pressurizing time and the cooling time for cooling while gradually releasing the pressurization, are decided to control a pressurizing control valve 11. Further, a pattern preset based on the molten metal temp. and the sprue temp. is selected, and the pressurizing time and cooling time preset from a data map combining the sprue temp. and the side die temp. according to the selected pattern are decided.