[目的]建立测定痕量铝的测定方法。[方法]利用分光光度计记录沸水浴中Al3+催化KBrO3氧化甲基红褪色前后的光密度。[结果]方法的线性范围为40～800μg/L,线性相关系数r=0.9989,检出限为8.0μg/L。[结论]建立了测定水中痕量铝的简单、灵敏、准确的催化动力学分光光度法。 [Objective] To establish a method for the determination of trace aluminum. [Method] The optical density of KBrO3 oxidized methyl red faded by Al3 + in boiling water bath was recorded by spectrophotometer. [Result] The linear range of the method was 40 ~ 800μg / L, the linear correlation coefficient was 0.9989, the detection limit was 8.0μg / L. [Conclusion] A simple, sensitive and accurate catalytic kinetic spectrophotometric method for the determination of trace aluminum in water was established.