A laboratory study was conducted to remediate petroleum contaminated soils using microwave irradiation, and the traditional method of electric heating was also used for comparison purpose. The feasibility of the microwave irradiation method was evaluated in aspects of the reaction time, petroleum removal efficiency and energy consumption level. Meanwhile, the impacts of microwave irradiation mode and soil conditions on petroleum removal efficiency were also investigated, with a thermodynamic model of soils specifically developed. The results showed that microwave irradiation was better than the traditional heating method in remediating petroleum contaminated soils with less energy consumed. Also, microwave irradiation time, microwave power, soil moisture content and soil petroleum content had all imposed significant impacts on the remediation efficiency, and the results obtained from the model were basically consistent with the experiment results. Therefore, the findings from this study are of significance in real-world applications of microwave irradiation for the remediation of petroleum contaminated soils.