BACKGROUND: Acute kidney injury (AKI) is a common and life-threatening complication following pulmonary endarterectomy (PEA). Our study aimed to investigate the risk factors associated with AKI and evaluate the correlation between serum myoglobin (sMb) levels and postoperative AKI. METHODS: We conducted a retrospective study involving 134 patients who underwent PEA at China-Japan Friendship Hospital. AKI was defined and staged according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria. RESULTS: During the study period, the incidence of postoperative AKI was 57.5%, and the associated mortality rate was 6.0%. Severe AKI was found to be significantly associated with worse short-term outcomes (P<0.05). Logarithmically transformed postoperative day (POD) 0 sMb levels were significantly associated with AKI [odds ratio (OR) =5.174; 95% confidence interval (CI), 2.307-11.603; P<0.001] and severe AKI (OR =4.605; 95% CI, 1.510-14.048; P=0.007), also had independent predictive value [area under the curve (AUC) =0.776 in AKI and AUC =0.737 in severe AKI]. The optimal cut-off values were 370.544 ng/mL for AKI and 419.473 ng/mL for severe AKI. Furthermore, albumin concentration was found to play a protective role in the development of severe AKI (OR =0.838; 95% CI, 0.716-0.980; P=0.027) when higher than 40.350 g/L. CONCLUSIONS: Our findings suggest that a high concentration of POD0 sMb may increase the risk of developing AKI following PEA surgery. Increasing albumin concentration could serve as an effective preventive measure against AKI.