Solvent Free Microwave Extraction (SFME) is a new and faster process with higher energy efficiency used to extract essential oils. Nevertheless, so far no modeling efforts have been found on the subject. In this work a predictive modeling approach to the microwave extraction of essential oils applied to the SFME is proposed. The model includes the interaction between electromagnetic energy and the material through the use of Maxwell's equations together with estimation of the dielectric constants. The evaporation of water from the plant is also simulated. The results indicate that it is possible to model this process with a predictive approach of the properties of the system. The microwave heating is underpredicted in the area closer to the walls, thus the evaporation resulting in simulations is lower than the measured values. Nevertheless, the results show a behavior very similar to the experimental values. (C) 2011 Elsevier Ltd. All rights reserved.