Abstract: A new and rapid method for determination of azithromycin by flow-injection coupled with chemiluminescence detection was developed, which based on azithromycin inhibiting effect on chemiluminescence system of luminol-KIO₄ in alkaline solution. The running conditions of FI-CL system were investigated. And the sampling detecting rate was about 109 samples/h. Under the optimum conditions, linearity for azithromycin was found in the range of 3.0 × 10^-8~ 9.0 × 10^-6 mol/L with the detection limit (R_SN= 3) of 1.6 × 10^-8 mol/L. The relative standard deviation（RSD）was found to be 3.8 % for 11 replicate determinations of 3.0 × 10^-7mol/L azithromycin. The proposed method has been applied for the determination of azithromycin in azithromycin capsule