The present invention relates to highly cross-linked UHMWPE, which is possessed of an improved oxidation resistance, as well as a method for making the same. The UHMWPE material of the current invention is combined with an anti-oxidant compound or a free-radical scavenger prior to formation. Once the UHMWPE with the added material has been formed and treated with gamma or electron bean irradiation, it shows an improved wear resistance and also a good resistance to oxidation. Such a material, is particularly interesting for the field of making replacement joint implants.