Abstract: Ethylenediamine functionalized graphene sheet/polypropylene-maleic anhydride grafted polypropylene (GS-EDA/PP-PP-g-MAH) composites were prepared by using solution compounding method. The structure and properties of graphite oxide (GO), GS-EDA and the composites were characterized by using FTIR, XRD, DSC, SEM and tensile test. The results indicate that the ethylenediamine (EDA) has been successfully grafted onto the surface of graphene sheet (GS), and hydrogen bond interactions which help GS-EDA disperse well in matrix happens between GS-EDA and PP-g-MAH during the compounding. DSC test shows that the crystallization peaks of GS-EDA/PP-PP-g-MAH composites move to higher temperatures due to the incorporation of GS-EDA.Tensile strength of GS-EDA/PP-PP-g-MAH composites increases and then decreases with increasing GS-EDA contents. With 0.5wt% mass fraction of GS-EDA, the tensile strength of composites approaches the ultimate value. Comparing to pure PP-PP-g-MAH and PP, the tensile strength increases by 24.7% and 17.5%, respectively. SEM observations show that GS-EDA disperses uniformly in matrix at low content but aggregates at higher incorporation.