Abstract: Taking glucose as CK and phenol sulfuric acid as chromogenic reagents, the saccharide content in ammonium lignin sulphonate was determined by means of phenol sulfuric method with UV spectrophotometer in 490nm section. The results showed that there was a significant linear correlation between the glucose content and the photometric value when the glucose concentration was in the range of 20～120μg/mL, the coefficient R2 was 09959, with precision RSD as 0.034%, stability RSD as 0.102%, recovery rate as 98.99%, recovery RSD as 0.871%, and the repetition RSD as 0.336%. It was indicated that the phenol sulfuric acid method for determining saccharide content in ammonium lignin sulphonate was a way characterized with simplicity, practicality, high precision, good stability and repetition with high recovery rate.