Objective: To compare the influences between precise and conventional hepatectomy on changes of T lymphocyte subsets in liver cancer patients. Methods: Forty-seven liver cancer patients were randomly divided into two groups, and underwent precise hepatectomy (precise hepatectomy group, 26 cases) and conventional hepatectomy (conventional hepatectomy group, 21 cases) respectively. The main clinical variables, and the pre- and postoperative CD3+, CD4+ and CD8+ levels as well as CD4+/CD8+ between the two groups were compared. Results: In precise hepatectomy group compared with conventional hepatectomy group, the operative time was prolonged, but the amount of blood loss, length of hospital stay and incidence of postoperative bile leakage and intra-abdominal hemorrhage were all reduced (all P<0.05); the postoperative changes in liver function parameters in precise hepatectomy group were superior to those in conventional hepatectomy group (all P<0.05). At postoperative day (POD) 7, the values of CD3+, CD4+ and CD4+/CD8+ were significantly decreased in both groups compared with their preoperative levels, but the decreasing degrees of them in precise hepatectomy group were significantly less than those in conventional hepatectomy group (all P<0.05), and the CD8+ values were slightly increased in both groups compared with their preoperative levels (both P>0.05); at POD 14 the values of all these T lymphocyte subsets in both groups returned to their preoperative levels. Conclusion: Precise hepatectomy is superior to conventional hepatectomy in protection of immune function, which thereby benefits the recovery of liver function in liver cancer patients.