Objective To examine the possible role of hepatocyte growth factor (HGF) in transdifferentiation induced by TGF ? 1 in cultured human renal tubular epithelial cell lines(HKC). Methods The HKC cells were divided into negative control, positive control, HGF group, HGF inhibition group, HGF delayed administration group. Then the expression of E cadherin and alpha smooth muscle actin(? SMA)of HKC cells were assessed by indirect immunofluorescence ,the expression of ? SMA mRNA of HKC cells were assessed by reverse transcriptase ploymerase chain reaction(RT PCR). Results HKC cells treated with TGF ? 1 present a clear fibroblast like morphology, loss of epithelial marker E cadehrin and de novo expression of ? SMA. Simultaneous incubation of HGF or delayed administration of HGF abrogated the ? SMA expression and E cadherin depression triggered by TGF ? 1 in HKC cells in a dose dependent manner. HGF also blocked morphologic transformation of tubular epithelial cells. Conclusion TGF ? 1 is a key mediator that regulates the transdifferentiation of tubular epithelial cells into ? SMA (+) myofibroblast, HGF can inhibit transdifferentiation of HKC cells induced by TGF ? 1 , Delayed administration of HGF effectively suppresses, and partially reverses myofibroblastic transition of tubular epithelial cells