Sulfate ion content in citric acid solution by turbidimetric analysis method was studied and established.The effects of wavelength,citric acid and polyvinyl alcohol(PVA) concentration on the stability time and absorbance intensity were analyzed in detail.Results indicated that the crystallization rate of BaSO4 precipitation could be enhanced by addition PVA in the citric acid solution,and the stability of suspension was improved by increasing the concentration of PVA.Also,the optimal absorbance wavelength was 440 nm and the optimal PVA concentration was 1.0g/L,citric acid solution was less than 3%.The linear range of standard curve was 2~24 mg/L,and its equation was expressed as A=0.010 6C-0.018 3(A is the absorbance and C is the mass concentration of sulfate,R2=0.997 6).The reproducibility RSD was 0.73% and the recoveries were 97.5%~102.9%.The analytical method established in this work can be applied to accurate and rapid determination of sulfate ion in the citric acid.