Objective To study the short term and long term response and the safety of the different doses of recombinant interferon alfa 1b(IFN? 1b) for the treatment of the patients with chronic hepatitis B and the predictive factors of the response. Methods 146 Chinese patients with chronic hepatitis B entered randomly into four groups. Three groups were given with IFN ? 1b 3 million unit (MU), 5 MU and 10 MU respectively. The control group was given placebo. The short term(ETR) and long term(SR 12) responses and side effect were observed. Selected nineteen items (host related, drugs related and virus related), which affected the response of IFN alfa 1b probably (host, virus and drugs, et al) were analyzed. Results The end treatment response (ETR) of the IFN ? 1b 5 MU therapy was 55.3%, and 10 MU was 58.1%. Both efficacy were higher than the group of 3 MU IFN alfa 1b (32.6%) and control therapy group (5.9%, P