Background Gemifloxacin is a fluoroquinolone antibiotic with broad spectrum of antibacterial activity.The aim of the study was to evaluate the comparative effectiveness and safety of gemifloxacin for the treatment of patients with community-acquired pneumonia (CAP) or acute exacerbation of chronic bronchitis (AECB).Methods We performed a meta-analysis of randomized controlled trials (RCTs) comparing gemifloxacin with other approved antibiotics.The PubMed,EMBASE,Chinese Biomedical Literature Database and the Cochrane Central Register of Controlled Trials were searched,with no language restrictions.Results Ten RCTs,comparing gemifloxacin with other quinolones (in 5 RCTs) and β-lactams and/or macrolides (in 5 RCTs),involving 3940 patients,were included in this meta-analysis.Overall,the treatment success was higher for gemifloxacin when compared with other antibiotics (odds ratio 1.39,95％ confidence interval 1.15-1.68 in intention-to-treat patients,and 1.33,1.02-1.73 in clinically evaluable patients).There was no significant difference between the compared antibiotics regarding microbiological success (1.19,0.84-1.68) or all-cause mortality (0.82,0.41-1.63).The total drug related adverse events were similar for gemifloxacin when compared with other quinolones (0.89,0.56-1.41),while lower when compared with β-lactams and/or macrolides (0.71,0.57-0.89).In subgroup analyses,administration of gemifloxacin was associated with fewer cases of diarrhoea and more rashes compared with other antibiotics (0.66,0.48-0.91,and 2.36,1.18-4.74,respectively).Conclusions The available evidence suggests that gemifloxacin 320 mg oral daily is equivalent or superior to other approved antibiotics in effectiveness and safety for CAP and AECB.The development of rash represents potential limitation of gemifloxacin.