To provide a die casting device in which a control unit for controlling a hydraulic circuit driving a hydraulic cylinder for injection can be constituted to have a simple structure and a flow rate control value for controlling working oil discharged from the hydraulic cylinder for injection into a tank can be minimized.

The flow rate control valve for controlling the flow rate of the working oil discharged from the hydraulic cylinder for injection into the tank when molten metal is injected, is provided with a first oil passing hole A set to communicate with a piston rod side in the hydraulic cylinder for injection, a second oil passing hole B formed to communicate with the opposite side of the piston rod in the hydraulic cylinder for injection, a third oil passing hole P formed to communicate with the hydraulic pump and a fourth oil passing hole T formed to communicate with the tank. Further, this control valve is constituted of 3 positions switching valve 100 having a spool 106 where the first oil passing hole A communicates with only the fourth oil passing hole T when a plunger is advanced, and the first oil passing hole A communicates with the third oil passing hole P and the second oil passing hole B communicates with the fourth oil passing hole T when the plunger retreats.