Abstract: Utilizing PP as matrix,GF and PET as reinforcing fibers,preform of plain fabric were woven and the thermoplastic composites were made by the hot pressing of lamination.On the basis of these composite samples,this paper studied the influence of the PP volume content on the thickness,the cross-section morphology,the impregnating degree of the resin and the tensile properties of composite sheet.The results indicate that: when the content of PP increases,the tendency for the thickness of the composite sheet will be downward clearly,while when the content of PP is over 60%,the change of the thickness will tend to be gentle.The content of PP is greater,the effect of resin coats and soaks reinforcing fibers is the better.However,the mechanical properties will be declined with the relative amount of reinfored fibers decreased.