AIM: To investigate the impact of renal dysfunction on clinical response to intravitreal conbercept injection (IVC) for diabetic macular edema (DME). METHODS: This retrospective study included a total of 100 eyes from 100 patients with DME treated with IVC with 3+PRN regimen. Based on the estimated glomerular filtration rate (eGFR), the patients were divided into normal renal function group (n=37), impaired renal function group (n=27), and renal insufficiency group (n=36). The main outcome measures were best-corrected visual acuity (BCVA) and central subfield macular thickness (CST). Clinical parameters included blood urea nitrogen, serum creatinine, serum uric acid, glycosylated hemoglobin (HbA1c), and hemoglobin. RESULTS: The mean follow-up time was 3.9mo. The mean number of IVCs was 2.07±1.22 in the three groups. Mean BCVA improved significantly from 0.81±0.49 logMAR at baseline to 0.72±0.52 logMAR in the three groups at the final visit (P<0.001). Mean CST decreased significantly from 427.85±148.99 µm at baseline to 275.31±108.31 µm at final visit (P<0.001). Patients in the normal renal function group had higher baseline hemoglobin levels and thinner baseline CST than those in the impaired renal function and insufficiency renal function group (all P<0.001). Patients in the normal renal function group had higher baseline hemoglobin levels and thinner baseline CST than those in the impaired renal function and insufficiency renal function group (all P<0.001). The three groups had no differences in baseline HbA1c levels (P>0.05). Good baseline BCVA (logMAR, P=0.001) and thicker baseline CST (P=0.041) were associated with visual acuity improvement. Higher eGFR (P<0.001), hemoglobin (P=0.032) and thicker baseline CST (P=0.017) were associated with macular edema retrogression in the conbercept-treated diabetic patients, which showed better anatomical response to IVC. CONCLUSION: Our results indicate that the renal dysfunction is the risk factor associated with the efficacy of IVC for DME.