Classical tensile tests were performed to determine mechanical properties of PP and PP/WF composites. The apparatus used for these tensile tests is a Zwick Z010 with a 10 kN load cell and a Clip-On extensometer for displacement measurements during modulus tests. These tests were performed according to the ISO 527 standard: the crosshead speed is set at 1 mm/min for the tensile modulus measurements, 50 mm/min for the break property measurements. Thus, Young modulus, strength and deformation were determined as a function of the reprocessing steps (P1, P3, P5 and P7). 5 measurements were carried out for modulus measurements and for strength and elongation at break measurements.