Abstract: The technical properties of a new high molecular weight PPS and rnethods of preparing middle-length fiber relnforced composites of this polyme:have been studied.It is made sure that suspension impregnatlon of fiber-felt process is an avallable method to make the new composlte.Epoxy is used as a bonder to bind up PPS and felt as well as a cover to prevent PPS from oxidatlon.Mechanical properties of the new composite are tested and the “Uniformity design”is used to find out the best technical parameters.The middle-length fiber reinforced thermoplastlc PPS composite prepared by this Process has better ProPerties than that prepared by the RFC process developed in the Dow Chemical Company.Especially, when the temperature is up to 250C,its tensile strength still remains 89MPa.