Objective The aim of the present study was to assess the influence of anemia on devel-opment of contrast-induced acute kidney injury ( AKI) after percutaneous coronary intervention.Methods The subject group consisted of 1026 patients who had undergone coronary intervention procedure between January 1,2008 and October 31,2009. A nonionic,low osmolality contrast agent was used in our la-boratory at this time. Serum creatinine values were measured before and within 48 h of administration of con-trast agents. Contrast-induced nephropathy was defined as an increase of 0. 5 mg/dl or 25% in serum creati-nine concentration over baseline within 48 h of angiography, anemia as hemoglobin ( Hb) < 120 g/L in women and < 130 g/L in men. Results Among the 1026 patients studied,32(3. 1% ) experienced AKI af-ter procedure. AKI occurred in 6. 3% of the anemic patients and 2.2% of the non-anemic patients (P <0. 01). The incidence of AKI increased with decreasing of baseline estimated glomerular filtration rate ( eG-FR)in both the anemia and non-anemia groups. In patients with baseline eGFR < 30 ml· mi-1·(1. 73 m2 ) -1 ,a high proportion of both anemic and non-anemic patients experienced (24. 6% vs. 18. 5% ).When baseline eGFR was 30-59 ml·min-1·(1. 73 m2)-1 ,the incidence of in anemic patients was 2-fold higher than in non-anemic patients (7. 9% vs. 3. 8% ;P <0. 05). The amount of the contrast agent adminis-tered was similar for AKI and non- AKI patients [ (182 ±46)ml vs. (176±48) ml,P>0.05) ]. Multivariate Logistic regression analysis found that baseline eGFR and baseline hemoglobin were independent predictors of AKI. When presence of anemia was introduced into the multivariate model instead of baseline hemoglobin, it was also showed a significant association with AKI. Conclusions Anemia increases the incidence of AKI in patients with moderate renal dysfunction. Patients with both preexisting renal insufficiency and anemia are at high risk of AKI. Baseline eGFR and baseline hemoglobin (or anemia) are independent predictors of AKI.