In the tobacco industry, filament dryers play a key production role. Due to the complex internal structure of the airflow roaster, it is difficult to measure the airflow movement directly, so in the factory production process, the operator often sets the relevant parameters based on personal experience. This makes the working condition of the air dryer similar to an opaque “black box”, and the research on this equipment is still in its infancy. The objective of this study is to use three-dimensional modeling software UG to build a model of airflow roaster in a tobacco factory in Yunnan, and to simulate and analyze the flow field inside the roaster with the help of fluid simulation software FLUENT, aiming at revealing its inherent working rules. This study will provide a valuable reference for the future technical improvement of the airflow dryer and the optimization of the production process.