During welding operation, a large amount of metal dust is generated during the fusion welding process. These dusts exist in the air in the form of aerogel, which seriously affects the environment. At the same time, the dust is an easily inhaled substance, which is harmful to the human respiratory system,skin, eye blood, etc., and seriously affect the health of workers.This article takes the actual workshop welding fume treatment project as the object, and studies the airflow organization form of the welding fume treatment system of tall workshops. Calculate and verify the rationality of the piping layout of the dust removal system with the aid of airflow simulation. At the same time,through the simulation data at different cross-sections, the blind spots of smoke and dust control are found, so as to determine the best air flow organization form and provide a reference for project design.