The effects of pro-hepatocyte growth factor (pHGF) on the changes of renal cellular proliferative cycle of partial hepatectomized rats were observed by flow cytometry (FCM). S phase fraction (SPF) of control rats (group A) accounted for 7.58% and increased gradually within 6 h, following a peak at 12th or 36th h after operation, but in pHGF-treated rats (group B) the peak appeared at 24th h after operation. Proliferation index (PI) of group A was 13.2% before partial hepatectomy, increased within 6 h and reached a peak at 12th or 36th h after operation, and in group B the peak appeared at 48th h after operation. There were significant differences in SPF and PI between two groups (P < 0.01). These findings suggest that pHGF may nonspecifically promote the DNA synthesis of renal cells.