Abstract: The photocatalytic degradation of organic compounds has attracted great attention.In this work，the photocatalytic activity of TiO2 was significantly improved via modification with reduced graphene oxide(RGO)．The RGO/TiO2 nanocomposite，with varying RGO contents，was firstly fabricated by a solvothermal method.X­ray diffraction，high resolution transmission electron microscopy，Fourier transform infrared spectroscopy and UV­Vis spectroscopy were performed to characterize the structure and property of the as­prepared RGO/TiO2 nanocomposite.Based on a methyl orange model，the influence from different factors，including the RGO content and catalytic time，on photocatalytic activities as well as anti­Escherichia coli ability of the RGO/TiO2 nanocomposite，was investigated.The results show the binding between TiO2 nanostructures and RGO planes with C－O－Ti bonds within the nanocomposite after being calcined at 180 °C for 6 h．The RGO/TiO2 nanocomposites consisting of an initial adding amount of 40 mg GO during synthesis process have a most enhanced photocatalytic degradation efficiency of as high as 50%.This might be due to the great adsorptivity of dyes，extended light absorption range and efficient charge separation properties.Also，a much improved anti­Escherichia coli ability of 93% was achieved by the same RGO/TiO2 nanocomposites.This work provides a new approach for the fabrication of TiO2­based nanocomposite as visible­light photocatalyst of high performance，and facilitates its application for photocatalytic degradation of organic compounds.