The　signal　intensity　and　spectrum　of　electron-spin　resonance　(ESR)　has　been　observed　in　silicon　nanowires　(SiNW＇s)　and　nano-crystalline　silicon　structure　based　on　JEOL　system　model　FA-100　at　around　9.4GHz,　microwave　modulation　frequency　was　stabilized　at　100KHz.　The　over-saturation　behaviors　of　signal　intensity　of　ESR　in　different　diameters　of　SiNW＇s　by　observing　the　microwave　power　and　analyzing　the　oxidation　related,　room　temperature　(RT)　and　77K　dependences　of　ESR　spectrum　in　different　magnetic　fields　and　microwave　powers　have　been　ascribed　that　they　come　from　the　different　defects.　The　defects　have　existed　in　silicon-based　materials　using　physical　behaviors　of　the　signal　intensity　of　ESR　we　have　obtained　because　of　the　influence　of　temperature　dependences,　different　microwave　powers　and　oxidized　sample　for　SiNW＇s.