Natural fibers reinforced composites (NFCs) have renewable and low cost advantages. In this paper, the tung oilanhydride (TOA) modified polypropylene (PP)/hemp fiber composites have been prepared by a melt-blended process. Thereaction between the tung oil anhydride and the as-treated hemp fiber make the TOA molecules to accumulate on the surfaceof hemp fiber and to form a TOA layer on the surface of hemp fibers, which is confirmed by the FT-IR and SEM analyses. The TOA layer improves the compatibility between PP matrix and hemp fibers. The elongation at break (EB) and impactstrength of the PP/hemp fiber/TOA composites are twice more than the PP/hemp fiber composites. Thermal analysis showsthe Toneset and Tmax of the composites increasing that reflects the thermal stability of the composites improved. The crystallineproperty reveals that the Tc moves to high temperature with the TOA or hemp fiber added in the blends. The DMA andrheology properties analysis indicate that the TOA layer improved molecular mobility of the composites and show a shearthinning effect.