Abstract: The invention provides a TFE polymer capable of providing stretched materials excellent in membrane homogeneity. The present invention is related to a tetrafluoroethylene polymer having stretchability and non-melt-processability and having a standard specific gravity of 2.140 to 2.165, wherein, with regard to the heat-of-fusion curve obtained by subjecting the tetrafluoroethylene polymer in the form of an unbaked polymer to be measured having no history of being heated to a temperature of 300° C. or higher to differential scanning calorimetry at a programming rate of 2° C./minute, the ratio between the amount of heat, S2 mJ/mg, absorbed within the temperature range of from the temperature T0° C., which is lower by 2.5° C. than the temperature Tp° C. corresponding to the minimum point on the curve (provided that 340?Tp?345), up to 350° C., and the amount of heat, S1 mJ/mg, absorbed within the temperature range of from 320° C. up to the above-mentioned T0° C., namely the ratio [S2/S1], is not lower than 0.90.