Objective Age is an important factor influencing the prognosis of anti-neutrophil cytoplasmic antibody-associated vasculitis. This study aimed to investigate the clinical features and prognostic factors influencing the treatment outcome of eosinophilic granulomatosis with polyangiitis (EGPA) in the elderly. Methods Clinical data of all patients diagnosed with EGPA at Peking Union Medical College Hospital from January 2000 to December 2015 were collected and retrospectively analyzed. The patients were divided into the elderly group (≥ 60 years old at diagnosis) and the non-elderly group (< 60 years old at diagnosis). Clinical features, results of laboratory tests, and all-cause mortality were compared between the 2 groups by independent samples t test, Mann-Whitney U test, Chi-square test according to different types of data. Cox proportional hazards modeling was used to assess the prognostic factors for mortality, and Kaplan-Meier survival analysis to estimate cumulative survival rate and draw survival curve. SPSS statistics 25.0 was used for data analysis. Results A total of 181 patients were enrolled, including 45 elderly patients (elderly group) and 136 non-elderly patients (non-elderly group). The elderly group had significantly higher serum creatinine concentration [(91.3±57.6) vs (79.0±75.6) μmol/L; P=0.022], lower hemoglobin level [(120.5±20.1) vs (134.7±50.0) g/L; P=0.007], higher erythrocyte sedimentation rate [(51.5±37.0) vs (35.5±36.8) mm/h; P=0.004], higher incidence of renal failure (24.4% vs 5.1%; P<0.001), and higher score of Birmingham vasculitis activity [(17.1±6.7) vs (14.2±6.9) points; P=0.016] when compared with the non-elderly group. The proportion of the patients with five-factor score ≥ 2 was significantly greater (40.0% vs 8.8%; P<0.001) in the elderly group than the non-elderly group, so was all-cause mortality (24.4% vs 9.6%; P=0.011). Age ≥60 years, cardiomyopathy, central nervous system involvement, gastrointestinal bleeding and immunosuppressive therapy were risk factors for mortality in the EGPA patients. Pulmonary embolism and methylprednisolone pulse therapy were associated with death for those ≥60 years old. Conclusion Age ≥ 60 years is an independent risk factor for death in EGPA patients. Clinicians should concern the adverse effects of pulmonary embolism and methylprednisolone pulse therapy in elderly EGPA patients.