Objective To explore whether hospitalized elderly patients with severe communityacquired pneumonia ( SCAP) have better outcomes if they are treated with dual-therapy consisting of a β-lactam/macrolide or fluoroquinolone.Methods A prospective study was conducted in patients with SCAP aged 65 years or older between January 2007 and January 2012. These patients were assigned to a combination therapy group or a β-lactam monotherapy group by the attending physicians. Time to clinical stability( TCS) and total mortality were calculated. Prognostic factors for death were analyzed. Results Among the 232 patients, 153 patients were given β-lactam/macrolide or β-lactam/ fluoroquinolone ( macrolide in 67 patients and fluoroquinolone in 86) , while 79 were treated with β-lactam monotherapy. Compared with the monotherapy group, the combination therapy group was associated with significant decreased TCS ( median TCS, 10 days vs. 13 days) , and lower overall in-hospital mortality( 24.2% vs. 43.0%, P lt;0. 01) . Compared with fluoroquinolone, macrolide use was associated with lower ICU mortality ( 14.9% vs. 31.4% , P lt;0. 01) . Simplified acute physiology score Ⅱ, pneumonia severity index, mutilobar infiltration, and β-lactam monotherapy were confirmed as independent predictors of death. Conclusion β-lactam/macrolide or β-lactam/ fluoroquinolone combination therapy, especially with macrolide, has superiority over β-lactam monotherapy in elderly patients with SCAP, and should be recommended.