In the present work, a novel method is introduced to prepare flexible photoelectrodes, based on polypropylene (PP) - TiO2 porous nanocomposite film, for dye-sensitized solar cells (DSSC). Highly-filled nanocomposite films, prepared by twin screw extrusion of PP and TiO2 nanoparticles, were uniaxially stretched up to 200% at elevated temperatures in order to obtain porous films containing a percolated structure of the nanoparticles. The nanocomposite films were sensitized by an inorganic dye (N719) and used as a photoelectrode in a sandwich-like DSSC. Mercury intrusion porosimetry, BET surface analysis and UV absorption technique showed that higher stretching ratio leads to higher porosity and dye uptake in the nanocomposite photoelectrode layer. Photo-electrochemical properties of the cells were analyzed by photocurrent-voltage (I-V) and electrochemical impedance spectroscopy (EIS). Both short circuit photocurrent (Isc) and open circuit voltage (Voc) increased with stretching ratio of the nanocomposite films. The results of this research can lead to the development of a cost-effective method for producing flexible DSSC at low temperatures.