A　novel　MWECR-CVD　system　with　hot　wire　assisted　has　been　developed　to　decreased　the　hydrogen　concentration　of　a-Si:　H　films　and　increased　the　stability.　The　main　role　of　the　hot　wire　is　to　increase　the　plasma　temperature.　Promote　the　decomposition　of　reaction　gas　thereby　to　increase　the　low-hydrogen　radicals　and　restrain　the　higher　silicon　reactive　species　which　are　critical　to　form　(SiH2)n.　The　radiation　from　the　hot　wire　also　increases　the　temperature　of　growing　surface　of　the　films,　which　strengthens　the　activation　of　the　surface　and　enhances　the　diffusion　of　hydrogen　atoms,　so　that　the　hydrogen　concentration　is　decreased　and　the　microstructure　of　the　a-Si:　H　films　can　be　improved.　The　experiment　results　show　that　the　hydrogen　concentration　of　a-Si:　H　films　by　using　this　system　can　be　reduced　to　about　4.5　at%,　and　meanwhile,　the　stability　is　increased　remarkably　and　the　photosensitivity　is　improved.