Abstract: Based on elaborating the working principle of the hydraulic speeding soft brake, the study analyzed the heating characteristics of the system in two conditions of non-braking and braking. By using Fluent software, the study simulated temperature fields of key components that electromagnetic directional valve in the non-braking condition and electromagnetic proportional relief valve and oil tank in braking condition. Then, the temperature changes of the internal fluid of valves and oil tank are obtained. The temperature monitoring test system of the hydraulic speeding soft brake is established and the temperature monitoring test is conducted. Also, the temperature changes of the system in two conditions of non-braking and braking are monitored and recorded. Simulation and test results show that the hydraulic loop of non-braking condition of the hydraulic speeding soft brake is approximate zero-damping loop for low heat. Also, they show that the balance oil temperature after thermal energy generated by hydraulic speeding soft brake in braking condition has been cooled through the valve and the cooling tank is far below the normal allowable value (80°C). The valves and oil tank in braking condition have good heat dissipation capability. The research results show that hydraulic speeding soft brake can effectively convert the heat generated by the system and improve the reliability of the system so that it can ensure a reliable braking of the conveyor.