Roasting is one of the most important steps of the nut processing. Drying is one of the important changes occurring during roasting of nuts. In this study, drying during thin layer roasting of hazelnuts was characterised. Hazelnut drying during roasting occurred in the falling rate period. Temperature dependence of the diffusivity coefficient was described by Arrhenius-type relationship. The activation energy for moisture diffusion was found to be 1891.6 kJ/kg. Thin layer drying characteristics of hazelnut roasting were satisfactorily described by empirical Thompson model with the linear temperature dependence. Further research about effect of initial moisture content, air velocity, air relative humidity and layer thickness on drying characteristics and quality of hazelnuts is necessary for optimisation of hazelnut roasting and development of hazelnut roasters.