采用流动注射夹层带进样方式研究了酚红法测定溴的化学条件和流路参数，所建立的方法具有灵敏度高、精密度好、试剂消耗量少和分析速度快的特点。在所选实验条件下，Ｂｒ－的质量浓度为０２～１００ｍｇ／Ｌ时有良好的线性关系，检出限和相对标准偏差（２０ｍｇ／ＬＢｒ－，ｎ＝１１）分别为０１１ｍｇ／Ｌ和０８８％，测定速度为６０～９０／ｈ。对化学试剂ＫＣｌ和ＮａＣｌ中的杂质溴进行了测定，加标回收率为９５％～１０５％。 The flow injection mezzanine band sampling method was used to study the chemical conditions and flow parameters of bromine by the phenol red method. The established method has the characteristics of high sensitivity, good precision, low reagent consumption and fast analysis speed. Under the selected experimental conditions, there was a good linear relationship between the concentration of Br- and 0.2 ~ 100 mg / L, the detection limit and relative standard deviation (20mg / LBr-, n = 11) 0  11mg / L and 0  88%, the measured speed of 60 ~ 90 / h. The impurity bromine in chemical reagent KCl and NaCl was determined, and the recoveries were 95% -105%.