In order to study the effects of epidermal growth factor (EGF) on proliferation of human peritoneal mesothelial cells (HMC) and repair repair of damaged human peritoneum, the mesothelial cells from human omentum were seperated and cultured in vitro. The authors assessed the expression of EGF-R on the surface of HMC with ABC immune histochemical method and tested the proliferation extent of HMC treated with EGF at different time and dosage levels with 3H-thymidine incorporation method. The results showed that EGF-R existed on the surface of HMC and EGF could stimulate the proliferation of HMC. The proliferation of HMC growing in the media containing 20 micrograms/L EGF was more significant than that growing in RPMI-1640 alone. The greatest proliferation index (PI = 8.16) of HMC appeared in the media containing 50 micrograms/L EGF. The proliferation of HMC stimulated by EGF was time- and dose-dependent. These studies indicate that the proliferation of HMC stimulated by EGF may play a very important role in the structral and functional recovery of the injured peritoneum.