Abstract: Ultrasonography(B mode)of liver and serum amino acid levels were studied in 15 cases of schistosomiasis japonica who had been cured for more than 5-15 years.Typical B ultraso nic images of hepatic fibrosis due to schistosomiasis were found in all patients which could be classified into three types,namely,the spotty type(Ⅰ),the tortoise shell type(Ⅱ) and the net patchy type(Ⅲ)according to the patterns of echogenic bands.Moderate to marked echogenic thickening of portal vein wall,and dilation of portal and splenic veins were revealed in patients with type Ⅱ and Ⅲ images. Free amino acids in sera were determined by using HPLC AAAS.The result revealed that the concentration of 8 nonessential and 3 essential amino acids(threonine,valine,tryptophan)were significantly decreased in the 15 patients.The ratio of aromatic to aliphatic amino acid was markedly elevated in 3 patients of type Ⅲ.The serum amino acid imbalance was at tributed to the severe hepatic damage and impaired liver function.