The alternatives for prophlaxis and treatment of recurrent hepatitis B virus infection have increased since new oral nucleoside analogues have become available. We conducted this experimental study to investigate the effect in the liver of these agents on the expression of transforming growth factor alpha (TGF-alpha) and on proliferation index, estimated by Ki-67. Thirty male Wistar albino rats were randomized into three groups: group A (n = 10) received adefovir dipivoxil (40 mg/kg/d per gavage); group B (n = 10), lamivudine (L; 30 mg/kg/d per gavage); and group C (n = 10) did not receive any treatment and were the control group. Groups A and B were treated for 3 days. Animal treatment began on day -1. After performing 70% partial hepatectomy on day 0, all rats were sacrificed on postoperative day 2 to harvest liver tissues for histopathological examination. We stained and indexed Ki-67 and TGF-alpha immunohistochemically on the hepatectomy surface and in the parenchyma, Ki-67 and TGF-a indices were significantly higher in group A compared with group B (P = .001 and P = .004, respectively, and P = .003 and P = .001, respectively). When the L group was compared with the control group for results on the hepatectomy surface and the parenchyma, Ki-67 and TGF-a indexes were insignificantly different (P = .6 and P = .3, respectively, and P = .1 and P = .6, respectively). Based on the results of this experimental study, we concluded that Adefovir dipivoxil has greater proliferative effect on liver parenchyma and in the cut surface than does lamivudine.