Abstract: In alkaline medium,prednisone acetate could enhance the intensity of chemiluminescence produced by the reaction between Ag(Ⅲ) complexes and luminol.Based on the fact,a method for determination of prednisone acetate by flow injecting Ag(Ⅲ) complexes-luminol chemiluminescence system was proposed.The optimized conditions found were as follows: ① concentration of sodium hydroxide in luminol solution:0.6 mol·L-1;② concentration of luminol solution: 8.0×10-7mol·L-1;③ concentration of sodium hydroxide in Ag(Ⅲ) complexes solution: 1.7 mol·L-1;④ concentration of Ag(Ⅲ) complexes solution: 5.0×10-5mol·L-1.Linearity range of prednisone acetate was found between 6.0×10-8 and 8.0×10-5mol·L-1 with detection limit (3s/k) of 2.9×10-9mol·L-1.1.0×10-6mol·L-1 prednisone acetate standard solution was tested for 11 measurements,value of RSD found was 2.9%.Values of recovery found were in the range of 100%-105%.