PurposeInflammation is commonly considered a mechanism underlying contrast‐associated acute kidney injury (CA‐AKI). This study aimed to explore the predictive capability of the novel inflammatory marker lactate dehydrogenase‐to‐albumin ratio (LAR) for CA‐AKI following percutaneous coronary intervention (PCI), and further compare it with other common inflammatory biomarkers.MethodsThis study enrolled 5,435 patients undergoing elective PCI. The primary outcome was CA‐AKI, and the secondary outcome was all‐cause mortality. All patients were grouped into three groups based on the LAR tertiles.ResultsThree hundred fifteen patients (5.8%) experienced CA‐AKI during hospitalization. The fully adjusted logistic regression suggested a significant increase in the risk of CA‐AKI in LAR Tertile 3 (odds ratio [OR]: 2.51, 95% confidence interval [CI]: 1.68−3.83, p < .001) and Tertile 2 (OR: 2.11, 95% CI: 1.42−3.20, p < .001) compared to Tertile 1. Additionally, receiver operating characteristic (ROC) analysis demonstrated that LAR exhibited significantly superior predictive capability for CA‐AKI compared to other inflammatory biomarkers. Regarding the secondary outcome, multivariate COX regression analysis showed a positive correlation between elevated LAR levels and all‐cause mortality.ConclusionIn patients undergoing elective PCI, LAR was significantly independently associated with CA‐AKI, and it stood out as the optimal inflammatory biomarker for predicting CA‐AKI.