Abstract: The co-polypropylene (PP) based composites with talcum powders and polyolefin (POE) were prepared by melt extrusion using a twin-screw extruder. The effects of POE content and storage time on mechanical properties of the composites were investigated, and the fractography of the composites was observed by scanning electron microscopy. The results indicated that a brittle-ductile transition occurred at POE content of 7 wt %. The impact strength of the composites increased gradually with the addition of POE over 11 wt %. There was little change in impact strength after the composites were stored for 24 h. The increase of POE content resulted in a decrease in the size of POE dispersed phase.