Abstract: In order to study the effect of the vacuum drying process of polyester chips on the moisture content of chips, this paper uses Fluent software to establish a vacuum drying model for polyester chips, and simulates the moisture content of chips under different process conditions. The results show that the higher the temperature, the higher the initial moisture content, the higher the vacuum degree, the smaller the stacking thickness, and the faster the average moisture content of the polyester chip layer decreases. The faster the drying rate is, the shorter the drying time required. The suitable process conditions for vacuum drying of polyester chips with different moisture content were obtained by using the model. The moisture content of polyester chips should be less than 50 mg/kg. When the initial moisture content is 2000 mg/kg, the chips can be tiled with a thickness of 10 mm, the temperature is 130℃, the vacuum degree is 100 k Pa, and the drying time is 20 h; when the initial moisture content is 8000 mg/kg, it can be tiled with a thickness of 5 mm, the temperature is 150℃, the vacuum degree is 100 kPa, and the drying time is 30 h.