Based on the Xin-Jiang red-fleshed apple, the drying characteristics of apple slices were studied in terms of hot-air temperature, slice thickness and hot-air velocity. Origin 8.0 software was used to analyze data and optimize the mathematical model of red-fresh apple slices drying. The result showed that there factors affected the drying characteristics, and hot-air temperature had the greatest impact. Increasing hot-air temperature and hot-air velocity, or decreasing the thickness of slice, the drying rate(DR) of red-fleshed apple slices increased. When hot-air temperature was 80 ℃, the slice thickness was 2mm, hot-air velocity was 1.5 m/s, drying rate of red-fleshed apple slices was the highest. It was showed that all 6 drying models could describe the moisture changes of red-fleshed apple slices during hot-air and thin-layer drying. Page model had the highest R2, the lowest root mean square error (RMSE) and χ2. Therefore, it was the optimum model.