The invention discloses an instant heating type automatic milk preparation machine, which comprises a milk powder quantitative supply device, a milk powder brewing device, a water tank, a hot water supply device, a control panel and a control circuit board, wherein the milk powder brewing device comprises a mixing bin, a powder inlet, a water inlet and a liquid outlet; the milk powder quantitative supply device comprises a milk powder box and a milk powder quantitative mechanism; the hot water supply device is connected between a water outlet of the water tank and a water inlet of the milk powder brewing device; cold water is fetched from the water tank and is heated into the hot water with preset temperature, and the hot water is conveyed to a water inlet of the mixing bin; the hot water supply device, the milk powder quantitative mechanism and the control panel are respectively and electrically connected with the control circuit board; an operation instruction is inputted via the control panel, and the control circuit board is used for controlling the running of the instant heating type automatic milk preparation machine. The instant heating type automatic milk preparation machine has the advantage that the instant heating function of the hot water for instant use can be realized in the automatic milk preparation process, so the electric energy can be saved, and the deterioration of water quality caused by repeated heating of the water in the water tank is avoided.