Objective  Effects of coenzyme Q₁₀ (CoQ₁₀) on mitochondrial permeability transition(MPT) of regenerating hepatocytes in rats were surveyed in this paper. Methods 120 Sprague-Dawely female rats were randomized to receive three different doses of CoQ10 by gastric lavage daily starting on the day of partial hepatectomy (PH). The rats were killed at different times and the livers were processed for mitochondrial suspension, which was tested with or without Ca ²⁺ induction by using spectrophotometer. Results During 6-48hours after PH, the mitochondrial permeability of the group treated with high dose（60mg/kg CoQ₁₀）was much lower than that of the control group. The group treated with low dose（6mg/kg CoQ₁₀）was much lower than the control at 48 hours only. However, no statistically significant difference was found among all the groups at 72 hours after PH and later; The mitochondrial permeability of each group was enhanced along with time after the mitochondrial suspension was induced by calcium ion, but the variation of the group treated with CoQ₁₀ was less than the control during 6-48 hours after PH. Conclusion Treating with proper dose of CoQ₁₀ may reduce the mitochondrial permeability of regenerating hepatocytes; the effects mainly take place at the phase of cell proliferation.