Benralizumab is a monoclonal antibody that targets interleukin-5 receptor α to deplete blood eosinophils and improve the clinical outcomes of allergic asthma. We conducted a meta-analysis to evaluate the safety and efficacy of different doses of benralizumab in patients with eosinophilic asthma. All randomized controlled trials involving benralizumab treatment for patients with eosinophilic asthma, which were searched in PubMed, Embase, and the Cochrane Library published until January 2017, as well as the rate of asthmatic exacerbation, pulmonary functionality, asthma control, quality of life scores, and adverse events were included. Randomized-effect models were used in the meta-analysis to calculate the pooled mean difference, relative risks, and 95% confidence intervals. Five studies involving 1951 patients were identified. Compared with the placebo, benralizumab treatment demonstrated significant improvements in the forced expiratory volume in 1?s (FEV1), Asthma Quality of Life Questionnaire scores, decreased asthmatic exacerbation and Asthma Control Questionnaire-6 (ACQ-6) scores. Benralizumab treatment was also not associated with increased adverse events. These findings indicated that benralizumab can be safely used to improve FEV1, enhance patient symptom control and quality of life, and reduce the risk of exacerbations and ACQ-6 scores in patients with eosinophilic asthma. Furthermore, our meta-analysis showed that benralizumab with 30 mg (every eight weeks) dosage can improve the health-related quality of life and appear to be more effective than 30 mg (every four weeks) dosage. Overall, data indicated that the optimal dosing regimen for benralizumab was possibly 30 mg (every eight weeks).