Abstract: An electrochemiluminescence (ECL) sensor for magnolol was developed based on tris(2, 2-bipyridyl)ruthenium (Ⅱ) (Ru(bpy)₃²⁺)-doped silica (RuDS)-urushiol composits film modified glassy carbon electrode (GCE).The ECL analytical performances of this ECL sensor for magnolol based on its enhancement ECL emission of Ru(bpy)₃²⁺ were investigated. The experimental parameters influencing the ECL intensity were studied. The analytical approach based on the system was developed under the optimum condition. The enhanced ECL intensity was linear with the magnolol concentration in the range of 8×10^-8-8×10^-5 g/L. The detection limit was 3.7×10^-8 g/L and the relative standard deviation was 3.5% for 8 μg/L magnolol(n=8). The good recoveries of melamine in the range of 99.8%-103% were obtained in synthetic magnolol mixture samples, which showed that the ECL sensor exhibited excellent repeatability and stability.