A novel sonochemical method for direct preparation of nanocrystalline antimony sulfoiodide (SbSI) has been established. The SbSI gel was synthesized using elemental Sb, S and I in the presence of ethanol under ultrasonic irradiation (35 kHz, 2 W/cm2) at 50 degrees C for 2 h. The products were characterized by using techniques such as powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), and optical diffuse reflection spectroscopy (DRS). The SEM and HRTEM investigations exhibit that the as-prepared samples are made up of large quantity nanowires with diameters of about 10-50 nm and lengths reaching up to several micrometers and single-crystalline in nature.