OBJECTIVE:To establish a diazotize solution-spectrophotometry for the determination of bilirubin in zhenhuang oral liquid.METHODS:The solution to be determined was added with diazotize solution and the absorbability was detected at a detective wavelength of533nm.RESULTS:The calibration curve was linear for bilirubin at the range of1.07~8.56?g/ml(r=0.9999).The average recovery of loading sample was100.2%(RSD=0.73%).CONCLUSION:The method is simple,reproducible,cost-effective and suitable for the determination and quality control of bilirubin in zhenhuang oral liquid.