Fabrication of composite materials has been traditionally achieved with the help of metallic molds to ensure proper shape. The development of new forming and molding processes is expensive because the molds to produce parts are made from highly polished metal which can take months to manufacture. These molds need to be tested to ensure high part quality for production. Molds that cannot produce parts to specifications will need to be scrapped and redesigned. Simulation of the mold surfaces and manufacturing process reduces the iterations to produce high quality parts. Forming process for prepreg materials was explored using simulations to study the evolution of defects during the composite forming and layup process. Material characterization of the prepreg materials provides the real properties required for simulation. Shear modulus, stiffness, friction, and peel strength for carbon/epoxy prepreg are determined experimentally for an eight-harness satin weave prepreg. A hemispherical punch and forming die was modeled. Results are presented for the final shape of the formed part and the nature of forming defects are observed.