The utility model relates to a vehicle water-storage type electric warm water heater for a motor train unit. A cylindrical warm water heater body is transversely arranged on a mounting bracket, and the outer wall of the warm water heater is wrapped with an insulation layer; a plurality of heating pipes are arranged in the warm water heater body, and a control box is arranged at one end part of the warm water heater body; a connecting cable is arranged on the control box, and an exhaust valve communicated with the hollow cavity inside the warm water heater body is arranged at one end part of the warm water heater body; an outflowing temperature controller, a signal indicating temperature controller and an over-temperature protection temperature controller are arranged on the connecting cable in the control box, wherein, the heating pipes connected in parallel are connected with the over-temperature protection temperature controller through a conducting wire, and the over-temperature protection temperature controller is connected with the outflowing temperature controller through a conducting wire; and the outflowing temperature controller is connected with a power supply through the connecting cable, and the outflowing temperature controller is connected with the signal indicating temperature controller through a conducting wire. The utility model has the advantages of simple structure, convenient maintenance and use, high pressure bearing capacity, high level of protection, and the like.