A laboratory microwave convection dryer was used to dry the hawthorn fruit, applying microwave power in the range of 270–630 W, air temperature in the range of 40–70C and air velocity in the range of 0.4–1.6 m/s. Five empirical drying models for describing time dependence of the moisture ratio change were fitted to experimental data and model parameters in equations were determined by multiple regression analysis. Results showed that the Midilli et al. with R2 = 0.9983, χ2 = 0.0033 and RMSE = 0.0485 had the best performance (among the five models tested) in predicting the moisture. The effective moisture diffusivity, which ranged between 9.29 × 10−10 and 8.81 × 10−9 m2/s, increased with the increase in microwave power and air temperature. The activation energy of samples was found between 12.25 and 27.90 kJ/mol. Maximum shrinkage (64.39%) was achieved at the air temperature of 70C, microwave power of 630 Wand air velocity of 0.4 m/s.
