The role of ALT as a predictor of liver injury has been questioned. The aim of this study is to use liver biopsy to assess the degree of liver injury in patients with chronic hepatitis B(CHB) whose ALT < 2 x upper limit of normal (ULN). A total of 49.2% of patients in this study had significant inflammation (grade >or=2) and 36.4% had significant fibrosis (stage >or=2). The frequency of serious inflammation and fibrosis was similar in patients with different ALT levels. The level of serum HBV DNA was not significantly associated with the extent of inflammation and fibrosis. Advanced age was a significant independent predictor of histological damage and the presence of more significant inflammation and fibrosis. We conclude that many CHB patients with ALT < 2 x ULN have significant liver inflammation or fibrosis and that liver biopsy is necessary to assess liver damage and should be used to assess the need for anti-viral therapy.