Abstract: Objective: To investigate the effect of intravenous hydration therapy in prevention of contrast-induced nephropathy(CIN) after percutaneous coronary intervention(PCI). Methods: One hundred and eighty cases of patients were divided into the control group (drinking water) and experimental group (intravenous hydration therapy). The levels of serum creatinine(SCr),urea nitrogen (BUN), serum β₂-microglobulin(β₂-mG),and urinary β₂-mG were compared between the two groups after PCI. Results: The levels of SCr, BUN,β₂-mG,and urinary β₂-mG were significantly lower in experimental group(n=94) than that in control group(n=86) (P < 0.01); CIN occurred in 3 cases of experimental group,but 10 cases of control group(P < 0.05). Conclusions: Intravenous hydration therapy can prevent the injury of kidney function and reduce the incidence of acute renal failure after PCI.