Abstract: Objective　To evaluate and improve the method for detecting urine and cerebrospinal fluid proteins by sulfosalicylic acid turbidimetry using automatic biochemical analyzer. Methods　The improved sulfosalicylic acid turbidimetry using automatic biochemical analyzer(I-SS assay) and its parameters were established. The precision，linear range and recovery rate were evaluated and compared with the traditional sulfosalicylic acid turbidimetry(T-SS assay). Results　The withinrun and betweenrum coefficients of variation(CV) were 1.2%-1.5% and 2.1%-3.5%. The linear range was 0.037-2.38 g/L. The recovery rate was 85.6%-109.2%. The correlation with the T-SS assay was Y I-SS = 0.980 4X T-SS +0.010 8， and the correlation coefficient (r) was 0.982. Conclusions　The I-SS assay is sensitive and accurate, and it is suitable to automatic biochemical analyzer.

Key words: Urine protein, Sulfosalicylic acid, Turbidimetry, Automatic biochemical analyzer