Abstract: The short glass fiber(SGF)+polyolefin elastomer(POE)/foamed polypropylene(FPP) composites co-modified with maleic anhydride grafted PP (PP-g-MAH) were prepared through post-foaming process.The effect of PP-g-MAH content on the cell morphology,microstructure and mechanical properties of composites was investigated.The results show that there was no obvious change on the cell morphology of the composites,but improvement in foaming effect was realized by the addition of PP-g-MAH with a 60% increase in cell density and the diameter uniform distributed.The interfacial bonding between SGF and matrix was enhanced.The flexural strength and compressive strength of the composites of the peak values could be obtained with 5wt% and 8wt% PP-g-MAH,respectively.The impact toughness declined gradually with the increase of the PP-g-MAH content.