A novel method of flow injection chemiluminescence for the determination of rifapentine was proposed based on the phenomenon that the chemiluminescence intensity of the luminol-K3Fe(CN)6 system could be enhanced by rifapentine in alkaline medium,combined with flow injection analysis technique.Under the optimal experimental conditions,the linear range of rifapentine’s detection concentration was 0.008-0.88 mg/L,the detection limit(3σ) was 1.2×10-3 mg/L,and the relative standard deviation(RSD,n=11) was 1.9% for rifapentine at 6.0×10-2 mg/L.The method was applied in the determination of rifapentine in both capsules and plasma with satisfactory results.