In order to evaluate the impact of the stretching temperature on the cellular morphology of cellular polypropylene (PP) based thin films, a series of PP films filled with spherical particles of calcium carbonate (CaCO3) and platy talc particles with weight concentrations varying from 15 to 35 wt.% were prepared by twin-screw extrusion then biaxially stretched under controlled stretching speed and three various temperatures of 152, 155 and 158°C. The corresponding stress-stretching ratio curves were recorded and the cellular morphology (average cell aspect ratio, average cell thickness, and average cell wall thickness) were analyzed from scanning electronic microscopy (SEM) micrographs. It was observed that higher concentrations (35 wt%) of bigger CaCO3 particles (12 μm) led to an increase in cell yield. For a stretching temperature of 150oC and CaCO3 concentration of 35wt%, the developed cells obtained had an average cell wall thickness of around 3.6 μm , an average cell aspect ratio of around 5.6 and an average cell thickness of around 13.6 μm, which was within the aimed specification for better piezoelectric performance, as defined by some models that relate the piezoelectricity coefficient d33 as a function of the cellular film Young modulus, its surface charge density and its relative permittivity. It was also demonstrated that stretching temperatures below 155°C enabled the delamination of the PP/CaCO3 interface, while it was not the case at 158°C.