The investigation relates to the influence of gamma -irradiation in vacuum on the changes in solubility and in thermomechanical and physicomechanical characteristics of tetrafluoroethylene plus vinylidene fluoride copolymers. It is found that with increase in the content of methylene units the crosslinking of the copolymer is more intense. Relationships of the tensile strength and elongation at break to the absorbed dose and testing temperature are quoted.