The preparation of beta-In2S3 nanomaterial was carried out by reacting In (NO3)3 with thioacetamide through hydrothermal process at 120 degrees C for 12 h. The size and morphology of In2S3 were characterized by the scanning electron microscope (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) while the degradation efficiency was evaluated by the photocatalytic degradation of oxytetracycline under natural sunlight. The results revealed that beta-In2S3 nanoparticles are made up of nanosheets with a length of 15-30 nm and with high efficient catalytic performance, in which more than 98% of the initial oxytetracycline (30 mg x L(-1)) was degraded in 4 h. Furthermore, the prepared pG-In2 S3 can be recycled and kept efficient catalytic performance above 85% even after reusing for four times, which reflected the good stability and relative photocatalytic activity of In2S3.