Abstract: To study the spreading process and rules of smoke during fires on underwater dry oil extraction devices, providing data and reference for emergency escape from underwater dry oil extraction devices, Pyrosim software is used to model the underwater dry oil extraction device in design, simulate and analyze the smoke diffusion and temperature change rules in the cabin under extreme conditions. Furthermore, the personnel evacuation escape simulation software Pathfinder is used to simulate the escape process of the operating personnel in the cabin during a fire. The study showed that when the airtight door was opened, smoke diffused outside the Christmas tree room at t=15 s; and when t=8 s, all escape personnel could reach the emergency escape cabin, at which time the smoke and smoke temperature were within a safe range, indicating that the evacuation of personnel in the underwater dry cabin met the requirements. By simulating the smoke and studying the evacuation of personnel during a fire in subsea dry-type oil production unit, it is possible to verify whether the design of the subsea dry-type oil production unit meets the needs of personnel evacuation, which is of great significance for the design and improvement of subsea dry-type oil production unit and for ensuring the safety of maintenance personnel.