The invention provides a device and a method for positioning a fault of urban rail transit overhead contact line equipment, wherein the device and the method relate to the field of power grid monitoring. The device comprises a DC transmitter, a double-side tripping device and a DC traction measuring and controlling protecting device. The DC transmitter detects current information and voltage information of the urban rail transit overhead contact line equipment and furthermore transmits the detected current information and the voltage information to the DC traction measuring and controlling protecting device. The DC traction measuring and controlling protecting device determines the position of the fault of the urban rail transit overhead contact line equipment according to the detected current information and the voltage information. The device and the method according to the invention have advantages of realizing high speed in finding the position of the fault, and improving fault positioning efficiency.