Graphene oxide (GO) membrane composed by GO nanosheets was obtained successfully using an  improved self-assembling bathing method. The structures and the properties of as-prepared membranes were modified by γ-ray irradiation. To evaluate the modification mechanisms, the pristine and irradiated membranes were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The results show that the interlayer spacing decrease from 0.94 nm to 0.80 nm and the mean thickness of GO nanosheets decrease from 1.69 nm to 0.86 nm after irradiation, which confirms that GO membrane can be reduced by γ-rays with the reduction of functional groups and decrease of interlayer distance. The deoxidization mechanism of γ-ray irradiation acting on GO membrane was also studied.Cited