Abstract: Abstract：The paper calculates the driving brake torque and the parking brake torque for the bidirectional driving vehicle in coal mine, in view of the fact that the traditional vehicles in coal mine may cause the brake failure further under the emergency braking state, the solution of multi-function wet-type brake is put forward. The structure and principle of the multi-functional wet-type brake are analyzed in detail, and the working principle and structural characteristics of the bidirectional driving vehicle braking system are expounded. Practice shows that the design of the hydraulic braking system is reasonable and feasible.