An ionic liquid/Silica sol/Nafion-Ru（bpy）2+3 modified gold electrode was prepared.The electrochemical and ECL characteristies of Ru（bpy）2+3 and levofloxacin at the modified electrode were studied，and the modified electrode exhibits good electrochemical activity and ECL response.Based on the obvious electrochemiluminescence sensitization effect of levofloxacin with Ru（bpy）2+3 in 0.1mol/L phosphate buffer，a new electrochemiluminescence method for the determination of levofloxacin hydrochloride was developed.Under the optimum condition，the calibration curve showed a good linearity with levofloxacin concentration in the range of 1.0×10-7-1.0×10-4 mol/L（r2=0.998 4） and the detection limit（S/N=3） was 1.59 ×10-9 mol/L.The RSD for 10 times determination of 2.2×10-5 mol/L levofloxacin was 3.6 %.The recoveries were in the range of 95.6%-103.5% and the RSD（n=5） was 3.0 %.The proposed method showed high selectivity，sensitivity and simplicity.This method was applied in the analysis of levofloxacin hydrochloride tablet with satisfactory results.