β-Cyclodextrin functionalized graphene/Ag nanocomposite (β-CD/GN/Ag) was prepared via a one-step microwave treatment of a mixture of graphene oxide and AgNO3. β-CD/GN/Ag was employed as an enhanced element for the sensitive determination of 4-nitrophenol. A wide linear response to 4-nitrophenol in the concentration ranges of 1.0×10−8–1.0×10−7 mol/L, and 1.0×10−7–1.5×10−3 mol/L was achieved, with a low detection limit of 8.9×10−10 mol/L (S/N=3). The mechanism and the heterogeneous electron transfer kinetics of the 4-nitrophenol reduction were discussed according to the rotating disk electrode experiments. Furthermore, the sensing platform has been applied to the determination of 4-nitrophenol in real samples.