Abstract: 1-vinyl-3-aminopropylimidazole tetrafluoroborate(VAPimBF₄) ionic liquid was successfully synthesized and characterized with H-NMR, FTIR and UV/Vis. A polymerized ionic liquid film modified glassy carbon electrode(poly-VAPimBF₄/GCE) was fabricated by using 1-vinyl-3-aminopropyl tetrafluoroborate ionic liquid as functional monomer, N,N'-methylene-bis-acrylamide as cross linker, ammonium persulfate and tetramethylethylenediamine as initiator, undergoing a radical polymerization process. Electrochemical behaviors of butylhydroxyanisole(BHA) were investigated by using voltammetry. The results indicated that the polymerized ionic liquid film could enhance the current response of BHA. Under the optimized experimental conditions, the oxidation peak current was linearly related to BHA in the concentration range from 1.0×10^-8 to 1.0×10^-5 mol/L with a low detection limit of 8.8×10^-9 mol/L(R_SN=3).