The power provided by the engine of the fire truck must match the power demand of the fire pump to ensure that the fire pump can run stably and efficiently. If the power of the fire truck engine is too small to meet the needs of the fire pump, the working efficiency of the fire pump will be affected, thereby affecting the extinguishing effect of the fire truck. If the power of the fire truck engine is too high, it will not only waste energy, but also cause the fire pump to fail due to excessive pressure, or even damage the fire pump. Therefore, a fire pump and engine power matching methods are proposed to ensure that the fire truck can run efficiently and stably during the fire extinguishing process, improve fire efficiency, and ensure the safety of firefighters and the public’s life and property. At the same time, it can also effectively save energy and improve the fuel economy of the fire truck. In this paper, the dynamic pressure calculation of fire pump is carried out by using the combination of empirical matching method and pressure flow method, and then using the obtained pressure data and flow data to preliminarily select the water pump; Then, according to the power of the pump and the theoretical speed of the engine obtained by the pre-selected speed ratio, the engine model is preliminarily selected. Finally, according to the external characteristic curve of the engine, the most suitable speed ratio is selected based on the power and torque.