Using Amesim software and based on the multiphase flow theory formula, a certain type of engine fire suppression system using Halon1301 fire extinguishing agent was modeled, and the accuracy of the model was verified by comparing it with its experimental data. Model and calculate the fire extinguishing system of a certain type of engine using HFC-125 fire extinguishing agent, and analyze the influence of parameters such as fire extinguishing agent filling pressure and fire extinguishing pipeline diameter on the spray flow rate and concentration of fire extinguishing agent. The results show that the flow rate of the engine fire extinguishing nozzle and the concentration of fire extinguishing agent in the engine core compartment increase with the increase of nitrogen filling pressure in the fire extinguishing bottle, but the increase is relatively small; selecting a fire extinguishing duct with a larger inner diameter within a certain range can significantly increase the flow rate of the engine fire extinguishing nozzle. At the same time, the spraying time of the fire extinguishing agent is significantly reduced. However, when the range is exceeded, selecting a larger inner diameter fire extinguishing duct will result in a smaller increase in the flow rate of the fire extinguishing nozzle and a smaller decrease in the spraying time of the fire extinguishing agent.