The flatbed microwave oven, unlike a turntable-equipped one, has a stationary ceramic plate inside the cavity, which allows more space for rectangular or larger dishes and is easier to clean. This newly designed microwave oven contains an aluminum antenna with irregularly shaped holes in the base that rotates during heating to achieve relatively uniform heating. Therefore, the complex configuration increases the difficulty of modeling the heating process, and no information has been available on this. This study investigated the heating characteristics of the domestic flatbed microwave oven by observing the temperature distributions in different foods during processing. A computational model based on the finite element method was also successfully established for predicting the temperature distributions in food by coupling an analysis of the electromagnetic field and heat transfer with a consideration of the rotation of the antenna during heating. Methods for optimizing the simulations to minimize the computational time using a geometric model and the food's dielectric properties were proposed. Finally, the simulations were compared with the experiments, and the RRMSE (relative root mean square error) and MRE (maximum relative error) values (material A of 2.27% and 6.53%, material B of 1.92% and 5.88%) demonstrated that they are in good agreement. (C) 2014 Elsevier Ltd. All rights reserved.