Objective To investigate the correlation between the expression of liver fatty acid binding protein (L-FABP) and acute renal injury in patients with acute myocardial infarction after emergency percutaneous coronary artery surgery. Methods 262 patients underwent percutaneous coronary artery surgery in our hospital from June 2018 to June 2019 were selected as the research objects. According to the occurrence of acute kidney injury after operation, they were divided into acute kidney injury group (n=86) and non acute kidney injury group (n=176). According to the stage of acute kidney injury (KDIGO), the acute kidney injury group was divided into stage Ⅰ (29 cases), stage Ⅱ (39 cases) and stage Ⅲ(18 cases). The levels of serum creatinine (SCR) and urinary L-FABP were compared by enzymelinked immunosorbent assay (ELISA). Receiver operating curve (ROC) was drawn to analyze and compare the diagnostic value of serum SCR and urinary l FABP in acute kidney injury. Logistic regression analysis was used to analyze the factors influencing the occurrence of acute kidney injury.Results The levels of serum SCR and urinary L-FABP in patients with acute renal injury were higher than those in non acute renal injury group (P＜0.05). Compared with stage Ⅰ, serum SCR and urinary l FABP levels were higher in patients with stage Ⅱ and stage Ⅲ (P＜0.05), and those in stage Ⅲ were higher than those in stage Ⅱ (P＜0.05). ROC analysis showed that the AUC of urinary LFABP in the diagnosis of acute renal injury was 0917, the sensitivity was 8020%, the specificity was 9170%, and the AUC of serum SCR in diagnosing acute renal injury was 0807, the sensitivity was 77.90%, and the specificity was 75.00%. Compared with the diagnostic value of serum SCR, the diagnostic value of urinary LFABP level was significantly improved. Logistic regression analysis showed that high level of SCR and high level of LFABP were risk factors of acute kidney injury.Conclusion The level of urinary LFABP increased significantly with the increase of acute renal injury stage after emergency coronary intervention, and urinary LFABP has a good diagnostic value for the occurrence of acute kidney injury after emergency coronary intervention.