The effects of microwave power and solvent.reactant dielectric properties on the kinetics of the decomposition of AIBN in n-butanol were investigated. According to the kinetic data, k increases with increasing microwave power, the dependence becomes stronger at high temperature. The Arrhenius parameters (Ea,mw, k0,mw) were higher than thermal counterparts. To elucidate the nature of microwave effect on chemical reactions, various models to relate the Arrhenius parameters to temperature, microwave power and the dielectric properties of the reaction medium were developed, nonlinear regression analysis was performed to estimate the model parameters and statistical analysis was conducted for model evaluation.