Microwave pyrolysis (MWP) is one focus of research and has drawn the widespread interest of foreign and domestic researchers. The applications of MWP include the pyrolysis of plastic waste, the pyrolysis of bio-mass waste, sewage sludge, and waste automotive engine oil, among others. The prevailing thermal gravimetric analysis technique is able to predict such thermal decomposition processes quite accurately, and is considered to be representative of conventional pyrolysis modeling. The heating rate of waste printed circuit boards material subject to microwave irradiation is determined by many factors, such as the sample's wave-absorption capacity and the heating effect from microwave-metal discharges. Two main differences can be easily observed between the microwave pyrolysis process and the conventional process: one is the sequence of events at the beginning of the pyrolysis reaction; the other one is the activation energy of the main pyrolysis phase.