Abstract : Our study addressed the 3D modeling of the infrared radiation reheating step and the stretch blow molding of cold injected preforms used for P.E.T. bottles. The goal was to calculate the full temperature profile of the preform at the exit of the furnace and the final thickness of the bottle at the end of the blow molding, using a single finite element numerical tool. The interaction between the halogens lamps and the semi-transparent material has been modeled using a ray tracing method, taking into account reflectors. The volumetric source term arising from irradiation and inserted in the heat assumption has been calculated through a Beer-Lambert law applied to each ray emitted by the tungsten filament or reflected by the ceramic. The preform rotation and translation have been modeled thanks to a mapping of the irradiative heat flux divergence calculated initially onto the configuration at the time considered. The study of the stretching and blow molding of the preform have given rise to the implementation of Mooney-Rivlin hyperelastic and G'Sell viscoplastic behavior laws. Numerical developments have been validated by a comparison with tensile tests, a thick tube and a thick sphere blowing analytical models. The remeshing method necessary for large strain and the contact algorithms accuracies implemented in Forge3® software allowed to demonstrate the feasibility of the 3D numerical modeling of stretch-blowing of P.E.T. preforms.