Abstract: A train running slope measurement device based on multi\|accelerometer fusion is proposed. The system measures the real\|time acceleration of the train through accelerometers of different angles, and combined with the accelerometer fusion algorithm, the slope value of the train position can be dynamically calculated. By using this method, the train does not rely on precise positioning and electronic map for overspeed protection, which improves the security and availability of the system, and is beneficial for popularizing and being integrated into the interoperable CBTC system.