Bismuth sulfide (Bi2S3) nanorods were successfully fabricated by sonochemical aqueous solution. The morphology, crystallinity and composition of samples at various growth stages were investigated by transmission electron microscopy (TEM), selected area electron diffraction (SAED) and X-ray diffraction (XRD). The results showed that the Bi2S3 nuclei had an obvious tendency to arrange themselves in rod-like arrays over extended length scales under soft template. Moreover the crystallinity would be reinforced with the elongation of the aging periods. The growth mode of particle−to−particle by self-assembly under soft template was proposed. The band gap energy of Bi2S3 nanorods was estimated at about 1.36 eV by UV-Vis absorption spectroscopy.