The invention discloses a transfer injection device and a transfer injection method for molten alloy. The transfer injection device is used for guiding a metal solution flowing out of a chute of a melting furnace into a standing furnace and comprises a supporting base, a transfer injection component and a driving component. The transfer injection component is connected to the supporting base. Thetransfer injection component is a pipe and is provided with an inflow port suitable for being connected with the chute and an outflow port suitable for being connected with the standing furnace. The driving mechanism is arranged on the supporting base and connected with the transfer injection component. According to transfer injection device, underflow can be formed in the transfer injection process of the molten alloy, and the molten alloy is prevented from making contact with air, so that air is prevented from being brought into the standing furnace in the transfer injection process of the molten alloy, air suction and oxidization of metal are reduced, and the purity of the molten alloy is ensured. In addition, the position of the transfer injection component can be adjusted through thedriving device so that the transfer injection component can be automatically adjusted extremely easily in the transfer injection process, and operation by workers is greatly facilitated.