The invention discloses an electronic rear axle brake valve which consists of a shell of the brake valve, an upper cover arranged on the shell, and an electrical appliance control box positioned on the upper cover, wherein a piston and a valve are arranged between the upper cover and the shell; an exhaust hole is arranged under the valve; the side of the shell is provided with an air inlet interface and an outlet interface; the shell is internally provided with an air inlet cavity and an air outlet cavity; an operating cavity is arranged between the upper cover and the piston; the outer side of the upper cover is provided with an operating interface which is communicated with the operating cavity; and control cavities are arranged among the upper cover, the piston and the shell. The outerside of the shell is provided with an electromagnetic air valve, an air inlet hole and an air outlet hole of which are respectively communicated with the air outlet cavity and the control cavities; the electrical appliance control box is internally provided with a singlechip control box and an air pressure sensor control box which are respectively provided with a singlechip electronic control circuit and an air pressure sensor control circuit; the singlechip control box is internally provided with a singlechip, a voltage stabilizer and a comparator; and the air pressure sensor control box is internally provided with an air pressure sensor, and the control circuit is connected with a load sensing switch under an automotive frame. The electronic rear axle brake valve is applicable to trucksand large buses.