A series of ethyl 6-bromo-5-hydroxy-1H-indole-3-carboxylates, 8a-11v, were synthesized and evaluated for their anti-hepatitis B virus (HBV) activities in 2.2.15 cells. The selective indexes of inhibition on replication of HBV DNA of compounds 11s (>8.7) and 11t (10.8), which were introduced halogen on the phenyl ring at position 2, were greater than those of the other evaluated compounds including lamivudine (7.0). Compounds 9e, 9h, 9l, and 11v exhibited significant anti-HBV activities, and the IC(50) values on replication of HBV DNA of these compounds were 3.6, 6.37, 5.2, and 5.4 microg/ml, respectively, which were far more potent than the positive control lamivudine 228 microg/ml.