目的:采用碘滴定法、酸碱滴定法、离子色谱法分别测定经硫磺熏蒸处理过的药材或饮片中亚硫酸盐的残留量,对三种方法进行比较。方法:采用三种方法,分别测定党参、山药、牛膝、白术四种中药,并进行回收试验,比较分析结果。总结各方法的特点和分析质量控制的基本要求。结果:碘滴定法和酸碱滴定法操作简单、成本低但干扰因素较多,因原理不同,适于不同品种药材测定。离子色谱法灵敏度高、专属性强但成本较高。结论:建议结合实际情况,选择适当方法进行二氧化硫残留量测定。 OBJECTIVE: To determine the residual amount of sulfite in medicinal herbs or pieces fumigated with sulfur fouling by iodate titration, acid-base titration and ion chromatography. The three methods were compared. Methods: Three kinds of traditional Chinese medicines of Codonopsis, yam, Achyranthes bidentata and Atractylodes macrocephala were respectively determined by three methods, and the recovery test was carried out to compare and analyze the results. Summarize the characteristics of each method and analyze the basic requirements of quality control. Results: The methods of iodine titration and acid-base titration were simple, low cost and more interference factors, which were suitable for the determination of different varieties of medicines due to different principles. Ion chromatography with high sensitivity, specificity, but high cost. Conclusion: It is suggested to choose the appropriate method for the determination of sulfur dioxide residue according to the actual situation.