Abstract: A novel agarose/ionic liquid/Nafion composite film modified glassy carbon electrode was fabricated based on the room temperature ionic liquids(RTIL) 1-Butyl-3-methylimidazolium hexafluorophosphate(PF6),agarose and Nafion.Ultraviolet-visible spectroscopy(UV-vis),Fourier transform infrared spectroscopy(FT-IR) and Cyclic voltammetry(CV) were used to characterize the composite film.Under the chosen condition,the concentration of H2O2 showed excellent linear relationships with the reducation peak current in the range of 8.0×10-7 ～ 4.8×10-5 mol/L,with a low detection limit of 1.0×10-7 mol/L(S/N = 3).