Tungsten　powder　was　prepared　in　NaCl-CaCl2-Na2WO4　system　by　molten　salt　electrolysis　method,　chemical　reactions　occurred　in　electrolysis　process,　and　electrolytic　products　were　analyzed　by　means　of　X-ray　diffraction　(XRD),　scanning　electron　microscopy　(SEM),　energy　spectrum　analyzer　(EDS)　and　differential　thermal　analyzer　(DTA).　The　anodic　process　and　overvoltage　were　investigated　using　cyclic　voltammetry　and　residual　electromotive　force　method.　The　results　show　that　tungsten　powder　could　be　synthesized　under　the　conditions　of　a　temperature　of　800°C,　a　cell　voltage　of　2.5　V　with　graphite　electrode,　calcium　tungstate　is　active　substance　in　electrolysis　process.　The　anodic　reactions　are　irreversible　and　the　kinetic　obstruction　of　anodic　process　should　be　controlled　by　the　anodic　chemical　polarization.