This paper reports the bulk synthesis route of the aligned and non-aligned high-qualityα-Si 3 N4 nanowires(NWs) which were grown directly from the Si substrate by vapor phase deposition at 1050℃.The as-grown products were characterized by employing XRD,SEM,HRTEM and photoluminescence.The microscopic results revealed that the products consist of single crystalline aligned and non-alignedα-Si 3 N4 NWs having a same diameter range of 30-100 nm and different lengths of about hundreds of microns.The XRD observation revealed that the products consist ofα-phase Si 3 N4 NWs.The room temperature PL spectra indicated that the NWs have good emission property.The non-aligned NWs were formed at lower temperature as compared with aligned NWs.Our method is a simple and one-step procedure to synthesize the bulk-quantity and high-purity aligned and non-alignedα-Si 3 N4 NWs at a relatively low temperature.The possible growth mechanism was also briefly discussed. This paper reports the bulk synthesis route of the aligned and non-aligned high-quality α-Si 3 N4 nanowires (NWs) which were grown directly from the Si substrate by vapor phase deposition at 1050 ° C. The as-grown products were characterized by XRD, SEM, HRTEM and photoluminescence. Microscopic results revealed that the products consist of single crystalline aligned and non-aligned α-Si 3 N4 NWs having a same diameter range of 30-100 nm and different lengths of approximately hundreds of microns. The XRD observation revealed that the products consist of α-phase Si 3 N4 NWs.The room temperature PL spectra indicated that the NWs have good emission property. non-aligned NWs were formed at lower temperature as compared with aligned NWs.Our method is a simple and one-step procedure to synthesize the bulk-quantity and high-purity aligned and non-aligned α-Si 3 N4 NWs at a relatively low temperature. The possible growth mechanism was also briefly discussed.