Objective To study the role of prostaglandin E1 in prevention of contrast-induced ne-phropathy (CIN)in elderly CHD patients undergoing PCI .Methods Three hundred elderly CHD patients who were going to undergo PCI in Tianjin Chest Hospital were divided into prostaglandin E1 treatment group (n=150) and conventional treatment group (n=150) .Patients in prostaglan-din E1 treatment group were treated with 20 μg prostaglandin E1 plus hydration therapy and those in conventional treatment group received simple hydration therapy .T heir serum levels of creatinine ,urea ,β2-microglobulin ,24 h proteinuria ,CRP ,IL-6 ,TNF-α,GPX ,SOD ,and creatinine clearance rate were measured before and 3 d after PCI .The incidence of CIN in two groups was analyzed .The hypotension events in prostaglandin E1 treatment group were recorded .Results The serum levels of CRP ,SOD ,GPX ,24 h proteinuria and the incidence of CIN were significantly lower while the creatinine clearance rate was significantly higher in prostaglandin E 1 treatment group than in conventional treatment group after PCI (P<0 .05) .The serum levels of CRP ,IL-6 , SOD ,GPX and 24 h proteinuria were significantly higher in two groups after PCI than before PCI (P<0 .05) .Conclusion Prostaglandin E1 can protect the renal function in CHD patients under-going PCI and play a certain role in preventing CIN .