Abstract: In order to explore a new way to solve overwintering problem of open-field soft seed pomegranate planting, a simple non-fixed cold-proof facility was designed and built．Aiming at daytime heat collection characteristics of facility in winter, ANSYS Fluent was used to establish a steady-state simulation model, and verification test was carried out．Then, the model was used to optimize facility parameters（air interlayer and diameter of ventilation hole）．Verification experiments showed that, relative error of Fahrenheit degree E_RE was less than 1‰, and tcoefficient of determination R² and root mean square error E_RMSE of temperature simulation values at monitoring points in the facility were 0.9625 and 1.19 K, indicating high reliability of the model．Optimization experiments showed that for cold proof facilities proposed, the best thickness of air interlayer was 3 cm, and the best diameter of ventilation hole was 14 cm．