To provide molten metal in a die cast machine at the optimum timing while the temperature drop of the molten metal in a ladle is controlled to a minimum.

A ladle 14 of a molten metal feeding device 3 feeds the molten metal in a melting furnace 1 to a pouring sleeve 23 of a die cast machine 2 while reciprocating between the molten metal ladling position P1 and the molten metal pouring position P2. The waiting time after pouring the molten metal until the ladle after finishing the pouring at the molten metal pouring position P2 starts the retraction toward the molten metal ladling position P1, is calculated by making a correction with the difference between the mean cycle time of N shot of the die cast machine 2 and the ideal cycle time with the waiting time before the pouring of the ladle 14 at the molten metal pouring position P2 is minimized as a reference. Even when the cycle time of the die cast machine 2 is fluctuated, the waiting time before pouring the molten metal at the molten metal pouring position P2 is prevented from being increased, and the temperature drop of the molten metal in the ladle 14 can be avoided.