PURPOSE: To provide a die for casting having an air vent structure which can easily remove the remaining flash in the air vent hole and can be suitably used to high pressure casting, etc.

CONSTITUTION: A vent pin 3 is inserted so as to be possible to slide in a through-hole 1a communicating a cavity space 6 arranged in a movable die 1 with the outer part of the die. The vent pin 3 has the air vent hole H demarcated with the vent pin and the wall face of the movable die 1 and communicating the cavity space 6 with the outer part of the die at the time of pouring the molten metal, and the air in the cavity space 6 is discharged to the outer part of the die from the air vent hole H at the time of pouring. The movable die 1 and the vent pin 3 can be displaced relatively with hydraulic cylinder 4 and a projecting part 5 is arranged as an insertable/extractable member in the air vent hole H by the relative displacement with the vent pin 3 in the movable die 1. At the time of separating the cast product from the die, the vent pin 3 is retreated by the action of the hydraulic cylinder 4 and the flash in the air vent hole H is removed by inserting the projecting part 5 into the air vent hole H.