Aim: To determine the effects of pentoxifylline, a methyl xanthine derivative on hepatic cell production of uninterferred lobe after portal vein branch ligation. Methods: Sixty-six rats were randomly allocated into 9 groups with 8 rats in PVL groups and 6 rats in sham operation groups. The portal branches of the median and the lateral liver lobes, corresponding to approximately 70% of the liver voluma were ligated in the PVL groups. The control group received 0.9% NaCl solution. The rats in the treatment groups received pentoxypilline at the dose of 50 mg/kg/dy. After 1,2,4 days of portal vein ligation in both PVL and PVNL lobes the levels of adenine nucleotides were determined and flowcytometric analysis of cell cycles were performed. Results: On the first day of portal branch ligation energy charge was significantly lower, in pentoxifylline treated group comparing to pentoxfylline untreated group, both in PVL and PVNL lobes (P < 0.05). Proliferative indexes were 0.38 and 0.29 in pentoxifylline treated and pentoxifylline untreated PVNL lobes respectively (P < 0.05). Conclusion: Pentoxifylline treatment resulted in an increase of percentage of calls entering mitosis phase on the first day after PVL, somehow accelerating the regenaration process.