Aim To investigate the effect of intra-aortic balloon pumping (IABP) on renal function in patients with acute ST-elevation myocardial infarction (STEMI) complicated by cardiogenic shock (CS). Methods A total of 103 patients with STEMI complicated by CS was randomized into control group (n＝51) and IABP group (n＝52). The clinical data were compared between the two groups. The incidence, severity, and 30-days survival rate of acute kidney injury (AKI), and the impact of IABP on AKI were observed in patients with STEMI complicated by CS. Results No significant difference was found in age, sex, medical history (including hypertension, diabetes, and complicated pulmonary edema), systolic blood pressure and mean arterial blood pressure at admission, heart rate, left ventricle ejection fraction, baseline serum creatinine, baseline evaluated glomerular filtration rate, door-balloon time, contrast agent dosage, and postoperative thrombolysis in myocardial infarction blood flow of patients between the two groups (P＞0.05). In the intravenous dose of dopamine and norepinephrine use rate, IABP group was lower than control group (P＜0.05). In the control group, AKI occurred mainly on the first day, while in the IABP group AKI occurred more on the second day, and there was no significant difference in the overall incidence of AKI between the two groups (P＞0.05). The renal replacement therapy (RRT) in the control group was higher than that in the IABP group (35.3% vs 17.3%, P＜0.05). The serum creatinine on the first day in control group was higher than that in IABP group (P＜0.05), but there were no significant differences between the two groups on the admission base value, the second day and the third day. There was no significant difference in the 30-days survival rate between the control group and the IABP group, while the 30-days survival rate of AKI patients was lower than that of non-AKI patients (P＜0.01). Conclusion IABP does not reduce the incidence of AKI and does not improve the 30-days survival rate in patients with STEMI complicated by CS, but it slows the rate of AKI progression and decreases the rate of RRT use in patients with AKI.