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Light-weight and highly-efficient microwave absorbers are highly demanded in both the stealthy field and the civilian field.Graphene is a novel two-dimensional carbon-based material and can be used as a promising candidate because of its excellent performance with controlled defects and adjustable conductivities.Here we demonstrate the microwave absorbing regulation of graphene oxide (GO) by the controlling of heating temperature and the thermal reduction degree.Single-layer GO was prepared by an improved Hummers method.Reduced GO (rGO) was prepared by heating GO at different temperatures under inert gas.Both GO and rGO were characterized using IR, XRD, Raman, XPS, TG and SEM.Oxygen-containing groups were removed gradually with the increase of heating temperature.Electromagnetic parameters indicate the recovery of graphene atomic layer with an increase of the permittivity.The results showed that rGO heated at different temperature have different absorbing properties.Relatively, rGO-400 have the best performance at the thickness of 3 mm and 4 mm.The qualified band widths (RL below-10 dB) are 5.4 GHz and 4.7 GHz respectively.rGO-200 have the best performance at the thickness of 5 mm and 10 mm, with the qualified band width of 6.1 GHz and 5.5 GHz respectively.