Abstract: The content of aluminum in ⁸⁹SrCl₂ crude material is an important parameter for quality control. The accurate measurement of that in ⁸⁹SrCl₂ solution is the basis of quality control and process improvement. In this paper, we use HR-ICP-MS to determine the aluminum content in ⁸⁹SrCl₂ solution, and we have established the method of sample preparation and constructing calibration curve, and the optimal mass spectrometry conditions were also determined. The effect of hydrochloric acid system, acidity and strontium matrix on the measurement of aluminum concentration were studied by a series of contrast experiments. Moreover, the source and the elimination method of mass spectrum interferences and aluminum background were also investigated by internal standard selection experiments. The experimental results show that the hydrochloric acid system has no significant effect on the measurement, and the 0.5% HCl system can be used as the matrix solution for standard and sample dilution. When the yttrium was selected as the internal standard, the double charged ion interferences and polyatomic ion interferences of aluminum could be eliminated with a resolution of 4 000 (10% valley), and the detection limit of this method could reach 39 ng/L. The method here can be used to measure the content of aluminum in ⁸⁹SrCl₂ solution quickly and accurately, which can meet the requirements of product quality control and process improvement.