Herein, we propose a novel in-situ membrane-based method for reducing GO using a VC aqueous reductant. With the support of density functional theory (DFT) simulations, we first verified the feasibility of using VC to reduce GO and further revealed the reaction mechanism behind the high reactivity between VC and GO. The rGO membranes and materials were characterized with contact angle, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM) and transmission electron microscopy (TEM). We thus suggested that with this novel method, GO sheets can be sufficiently reduced by VC under a highly laminate-confined environment in GO membrane (GOM) and largely remain their morphology.