PURPOSE: To enable use of low wear resistance equipment, by so constituting as to blow air from a blow hole provided separately after charging sand into a frame and apply compressive pressure while moving the sand in a direction leading to the exhaust hole in a match plate.

CONSTITUTION: Sand 10 is charged into a lower frame 7 from a sand hopper 1 by utilizing spontaneous gravity, a match plate 6 is put on, and an upper frame 4 is placed thereon. Similarly, sand 10 is charged from the hopper 1, and a holding plate 3 which is commonly used as upper blow hole is moved onto the frame 4. By pushing up by means of the plate 3 and a lifting plate 8 which is commonly used as lower blow hole, while compressing with a piston 9, air is blown in through blow holes A, B to scatter the sand 10. At the same time, the air is discharged from an exhaust hole C through exhaust pores, thereby compression-molding. Therefore, even in positions where sand filling is poor with respect to a model 5, sand moves due to air blow, so that a sand mold of uniform hardness may be formed. Besides, since there are multiple air blow holes, the friction of sand with respect to a model is dispersed and decreased, and high-speed moving distance of sand is decreased. Hence, equipment of low wear resistance may be used.