A survey was made of the influence of irradiation sterilization on relevant natural, semisynthetic, and synthetic polymers used for drug carrier system. The first part of the review deals with some general aspects of irradiation treatment and its use in the sterilization of pharmaceuticals. The second part reviews the information available in the literature on polymeric biomatenals used for carriers after irradiation sterilization. The influence of irradiation sterilization has been described for polyester, poly(ortho ester), different synthetic hydrogels, silicone derivatives, cellulose-derivatives, hyaluronic acid, different glucosides, collagen, and gelatine. Also, some limitations concerning the use of high-energy radiations for sterilization are given.