[en] Influence of electrons irradiation with energy 2 MeV on mechanical strength of thin polymer films such as: polyethylene-terephthalic, polyimide, fluoride-plas, pehnyl ones are studied. Structural changes in irradiated polymers are examined by the method of IR-spectroscopy. Elementary analysis is conducted and molecular mass of indicated polymers are measured. During study of dose dependences of polymer films' strength characteristics it was defined, that from 4 kinds of polymer films the least steady to irradiation have fluoride-plas film, and most steady have polyimide one, e.g. most radiation-stabile are polymers having in structure cyclic grouping (benzene ring, imide group). Comparison of results of IR-spectroscopy and chemical analysis with change of polymer films' strength is carried out. Correlation between structure changes and polymers' strength under irradiation is revealed. It was shown, that for examined polymers strength decrease is conditioned by destruction processes corresponding with reduction of molar mass as well as oxygen content in its