A novel method for the detection of sodium tanshinon ⅡA sulfonate was developed based on the inhibition effect of sodium tanshinon ⅡA sulfonate on luminol-H2O2-silver nanoparticles(AgNPs)chemiluminescence(CL) under alkaline condition.The optimal experiment-conditions were established by optimizing the concentration of CL substrates,reaction medium and its concentration,and the concentration of AgNPs.The possible mechanism of the CL system was also investigated.Under the optimal conditions,the CL intensity was inversely proportional to logarithm value of sodium tanshinon ⅡA sulfonate concentration in the range of 5.0×10-6-0.08 mol/L with a detection limit of 9.38×10-7 mol/L and a detection time of 20 s.With a considerable sensitivity and a wide detection range,the proposed method could be applied in the simple and fast detection of sodium tanshinon ⅡA sulfonate in the injection solution with satisfactory results which are in good agreement with the reference values obtained by high performance liquid chromatography.