Drying characteristics of walnut were determined experimentally as a function of temperature, air velocity and variety (Serr, Pedro, Z67, K82). Four different drying models were fitted to the experimental data to select a suitable mathematical form of the drying curve. Experiments were performed at air temperatures of 32 and 43°C and two air velocities of 1 and 3 m s-1 at each temperature. Of the drying models tested, the Page model was selected as the best mathematical model based on the values of R2, 2 and RMSE. Drying time and Page model constants were significantly dependent on the variables studied. Correlations of the Page model constant, k and m, the effective moisture diffusivity of walnuts and the drying time with the variables were determined. The effective moisture diffusivity of walnuts varied from 3.54×10-7 to 9.92×10-7 m2 s-1.