BACKGROUND/AIMS: The cirrhotic liver has been shown to regenerate after hepatectomy based on the findings of various imaging techniques. However, little has been reported so far regarding the restorative process using the liver function test in a long series after hepatectomy of both normal and injured livers. METHODOLOGY: A retrospective review was performed of 48 patients who underwent hepatic resection due to either primary or secondary liver cancers. They were histologically divided into three groups of 6 normal, 23 chronic hepatitis and 19 cirrhotic liver patients. In addition, the hepatitis group was divided into two groups according to the resected volume, which were 16 of a small resected volume and 7 of a large volume. For these patients, both a complete blood count and normal liver function test were performed before operation, and 7 and 14 days, 1, 3, and 6 months, and 1, 2, and 3 years, postoperatively. RESULTS: In the normal patient group, almost all test results recovered to their preoperative levels by 14 days to 1 month postoperatively. In the cirrhotic group, however, the red blood cell count and hematocrit levels did not recover to preoperative levels until 3 months postoperatively, while the GPT levels, the total bilirubin and albumin all recovered by one month postoperatively. However, the total cholesterol level needed 6 months to recover. In the large resection hepatitis group, the GPT level needed 7 days to recover, while the albumin and total cholesterol level needed three months to do so. In addition, the platelet level decreased significantly at 3 months postoperatively and thereafter it seemed to remain at a lower level. CONCLUSIONS: We demonstrated that a hepatic resection in patients with chronic liver disease requires a longer period of time to recover to preoperative levels based on the type of underlying liver parenchymal disease and the extent of resection.