The invention discloses a device applicable to exploring the thickness range of a brake pad and a manufacturing method thereof. The device comprises a supporting body, resistors, guide wires and a port. The top ends of parts of the guide wires are in an arc shape or a sharp corner shape to be fixed to the supporting body; the top ends of another parts of the guide wires are fixed to the supporting body; the end point positions of the guide wires are determined by the positions corresponding to the thickness needing exploring after the device and the brake pad are assembled; the number of the guide wires is two or more; and the parts of the guide wires can communicate with other guide wires only when making contact with a metal brake disc. According to the device, when the brake pad is rubbed to a certain thickness, the corresponding parts of the guide wires in the device can be disconnected due to friction, and parts of the guide wires can communicate with other guide wires when making contact with the metal brake disc, and accordingly the resistance value of a circuit can be varied when the brake pad makes contact with the brake disc and when the brake pad does not make contact with the brake disc; and due to the fact that the variation of the resistance corresponds to the thickness of a friction material, the thickness of the friction material can be determined.