Currently, traditional fossil energy is gradually exhausted for sustainable economic development, and environmental protection is an urgent requirement for all countries. Therefore, the issue of saving energy, as well as exploiting renewable energy sources, is being prioritized for development. The braking system collects dynamic energy, also known as the regenerative braking system, which is understood as the brake system; instead of converting kinetic energy into heat, the brake system can collect and store energy. The brake system of the bus in use is usually frictional. During braking, this type of brake system converts the vehicle's kinetic energy into heat, dissipates it into the surrounding environment, and cannot be recovered. Moreover, due to the operational characteristics, the bus has high stopping frequency and high braking capacity, leading to wasted energy, in addition to producing many emissions causing environmental pollution. This study focuses on experimental research for evaluating the dynamic energy acquisition of the mechanical brake system on a school bus as a function of operating parameters such as vehicle speed according to gears, vehicle mass as well as hydraulic pressure parameters. The results are noticed that the highest dynamic energy recovery rate is about 35% in the lowest gear. In the case, from the initial braking velocity of 30km/h to 0 km/h, the initial working pressure of the hydraulic tank is 100bar, the dynamic energy recovery rate is about 25%.