The effects of pHGF on the changes of hepatocyte proliferative cycle and liver regenerative capacity after partial hepatectomized rats were observed by flow cytometry (FCM). The results were as follows: 1) S phase fraction (SPF) in group of normal rats (group A) accounted for 9.89% and increased gradually within 6 h, following a peak at 12th h or 36th h after operation, but in the group of pHGF-treated rats (group B) the peak appeared at 24th h after operation; 2) Proliferation index (PI) of group A was 19.6% before partial hepatectomy, increased to 34.91% within 6 h and reached a peaks at 12th or 36th h after operation, and in group B the peak appeared at 48th h after operation. There were significant differences between two groups in SPF and PI (P < 0.01). The weight of liver began to increase 12 h after operation, and almost reached the preoperative weight 5 days after operation. These findings suggest that pHGF can promote the DNA synthesis and segmentation of hepatocyte.