Objective To assess the liver histopathological characteristics of chronic hepatitis B (CHB) patients with alanine aminotransferase(ALT)lower than 2 times the upper limit of normal (ULN) through liver biopsy, and try to provide subjective evidence for clinical anti-viral treatment.Methods From October 2005 to August 2010, patients accepted liver biopsy in department of infectious disease, Sichuan provincial people's hospital were enrolled. The criteria for liver biopsy was as follow, (1) HBsAg-positive for more than 6 months, (2) HBeAg-positive patients with HBV DNA ≥103 copies/ml or HBeAg-negative patients with HBV DNA≥ 104copies/ml, (3) ALT was lower than 2 times ULN for more than 6 months,and without any hepatic protectants, (4) never accepted any antiviral treatment before, including IFN or nucleoside analogues, (5) willing to accept liver biopsy. Before liver biopsy, routine blood test, prothrombin time, liver function test, hepatitis B antigen and antibody test, HBV DNA quantification were examined. The biopsy position was located under routine ultrasound, liver biopsy were performed to assess the grading of inflammation and necrosis and the degree of fibrosis. The correlation between all the factors and liver inflammation and fibrosis were analyzed. Results Totally 383 cases (240 males and 143 females) met the diagnostic criteria, aged from 16 to 59 years old and the mean age was 28.0 years old. Cases of liver inflammation in G0, G1, G2, G3andG4 grade was 2 cases (0.5％), 165 cases (43.1％), 191 cases (49.9％), 25 cases (6.5 ％ ) and 0 cases (0 ％ ) respectively, cases≥G2 grade accounted 56.4 ％ of total. Meanwhile,stage of fibrosis in S0, S1, S2, S3 and S4 was 103 cases (26.9％), 265 cases (69. 2％), 13 cases (3.4％), 2 cases (0.5％) and 0 cases (0％) respectively, percentage of liver fibrosis in S2stage and over was only 3.9％. The occurrence of serious liver inflammation was associated with age, ALT levels, HBV DNA levels and HBeAg status (P＜0.05). There was no obvious association between HBV DNA level and liver fibrosis (P＞0.05). Conclusions There were obvious liver inflammation and different degree of liver fibrosis in CHB patients with alanine aminotransferase(ALT)lower than 2 times ULN. The degree of liver injury assessed by liver biopsys is recommended as an evaluation for the necessary of anti-viral therapy.