Abstract:Natural exposure tests on PTFE membrane material were carried out in Harbin. The tensile strength, rupture elongation rate and tear strength of the material after 1,2,4 and 7 a were measured. The expressions of relations among the tensile strength, the tear strength of PTFE membrane material and time were fitted from measured data. Thus, valuable data are offered for evaluation on the weather ability of PTFE membrane material in Harbin.