Recently, wheat gluten has been investigated for potential use in non-food applications such as biopolymers and biocomposites. Interestingly, gluten biopolymer materials have promising mechanical properties with modulus and strength comparable with synthetic resins such as epoxy. Some modifications on gluten molecules have been implemented which give strength improvements of 50% compared to the initial gluten material. Moreover, the combination between gluten biopolymers and unidirectional natural fibers, particularly flax fibers allows obtaining high mechanical performance biocomposites. Prepreg processing technology has been developed to improve the impregnation with the gluten powders. The first results show a very high efficiency factor, meaning a measured modulus value which is close to the theoretical value while the measured strength value is above half of the theoretical strength. With this novel processing technique, we would obtain high mechanical performance together with having a 100% renewable material, which can also be recycled or composted at the end of its life.