The invention discloses a braking unloading prefill valve group. A first pressure measuring connector, a second pressure measuring connector, a safety valve, a second one-way valve and a hydraulic control reversing valve are arranged on the surface of the upper portion of a valve body; a conversion shuttle valve and a first one-way valve are arranged on the first side face connected with the surface of the upper portion, and an unloading valve is arranged on the second side face opposite to the first side face; and an oil outlet A and an oil outlet B are formed in the third side face, the third side face is adjacent to the first side face and the second side face, and a pressure sensor, an oil return port T and an oil supply port P are formed in the fourth side face opposite to the third side face. According to the valve group, the safety valve, the hydraulic control reversing valve, the pressure sensor, the first one-way valve, a second one-way valve, the unloading valve, the conversion shuttle valve, the first pressure measuring connector, the second pressure measuring connector, a port P, a port T, a port A, a port B and other components are integrated on one base body, and the valve group is lighter in mass, more compact in structure, more rapid in response and higher in response precision; and the functions of automatic liquid filling of two oil ways and unloading after liquid filling are completed can be achieved.