Objective To evaluate the effect of revascularization of the renal artery on urinary microglobulin in patients with coronary artery disease and significant renal artery stenosis (RAS). Methods Forty-four patients with coronary artery disease and severe RAS (luminal narrowing >70%) underwent percutaneous transluminal renal artery angioplasty (PTRA) and stenting, as well as percutane-ous coronary intervention. The urine -microglobulin ( o^-MG) and P2-Cmicroglobulin (P,-MG) at baseline and at 3 months after the procedures were measured. Procedural success rate, procedural complications, serum creatinine concentration at baseline and at 3-months were also recorded. Results At 3-months after the renal revascularization therapy, there was no significant change of urine o^-MG compared with that of the baseline, however, the urine (3,-MG decreased significantly 3-months after the treatment (237+ 187^g/L vs 377±173 |J.g/L, P<0.01). Multivariate analysis revealed that persistent elevation of urine was an independent predictor of severe events (including re-admission and renal failure) after renal revascularization therapy in patients with severe RAS (OR=3.01, 95% Cl 1.01-8.95, P=0.036). Conclusions In patients with coronary artery disease and severe RAS, revascularization with PTRA and stenting may improve renal tubular function, but a continuous high level of urinary microglobulins after intervention is associated with more frequent re-hospitalization and renal failure.