A polymer composite material based on polypropylene resin reinforced bamboo fiber was prepared and its mechanical properties were also tested. The resutls show the tensile, flexural and impact strengths increased with bamboo fiber content till 60 percent. Moreover, the rising rate became remarkable only at fiber content higher than 40 percent. The maximal values of tensile, flexural and impact strengths were reached at 60 percent of fiber content and equal 52.0 MPa, 67.7 MPa and 22.6 kJ/m2, respectively. Higher fiber contents do not lead to higher mechanical properties because of the lack of matrix materrial. In addition, the fiber dimensions have the obvious effect on composite properties: the mix fibers with different lengths may be influence the better mechanical properties to composite than continuous or short fibers. Water adsorption strong decrease mechanical properties of composite and this decreasing can reach the values of 33-42 percent after 60 days of immersion.