Microwave curing technologies have many advantages over the traditional thermal curing methods for the manufacturing of fiber reinforced polymers, especially the processing speed and energy efficiency. Energy can be instantaneously transferred through applied electromagnetic fields and heat is generated based on dipolar rotational interactions. Microwave curing processes have been used for glass fiber composites but there are significant challenges associated with microwave curing of carbon fiber composites. Efficient heating may be difficult due to high dielectric loss associated with carbon fibers. Laminate quality will be highly dependent on the uniformity of the electromagnetic field in the material. In this work, a multiphysics three-dimensional model was developed to study the composite curing behavior and temperature distribution of the laminate in the presence of microwave radiation. Microwave heating depends on the thermal conductivity, convective heat transfer, surrounding temperature, intensity of the electromagnetic field and the geometry of the sample. Required parameters are determined using experiments. The anisotropic properties of a composite were incorporated into the simulation model. This model can be used to optimize process parameters to cure thick and complex shaped composite parts. A cure cycle optimized to the microwave energy was developed and compared to the traditional thermal cure cycle.