Background: OnabotulinumtoxinA is widely used in treating neurogenic detrusor overactivity (NDO). We carried out a systematic review and meta-analysis to assess the efficacy and safety of the drug for treating NDO. Methods: We searched the following databases: Medline, EMBASE, and the Cochrane Controlled Trials Register. All published randomized double-blind, placebo-controlled trials of onabotulinumtoxinA for the treatment of NDO were identified in the analysis. The reference lists of the retrieved studies were also investigated. Results: Four publications involving a total of 807 patients were identified in the analysis, which compared onabotulinumtoxinA with placebo. The changes of the mean number of urinary incontinence per week (the standardized mean difference [SMD] = -10.91, 95% confidence intervals [CIs] = -14.18--7.63, P < 0.0001); maximum cystometric capacity (SMD = 146.09, 95% CI = 126.19-165.99, P < 0.0001) and maximum detrusor pressure (SMD = -32.65, 95% CI = -37.83--27.48, P < 0.0001) indicated that onabotulinumtoxinA was more effective than the placebo, despite the doses of onabotulinumtoxinA. Safety assessments primarily localized to the urinary tract indicated onabotulinumtoxinA were often associated with more complications. Urinary tract infections (relative risk [RR] = 1.48, 95% CI = 1.20-1.81, P = 0.0002); hematuria (RR = 1.81, 95% CI = 1.00-3.24, P = 0.05) and urinary retention (RR = 5.87, 95% CI = 3.61-9.56, P < 0.0001). Conclusions: This meta-analysis indicates that onabotulinumtoxinA to be an effective treatment for NDO with side effects primarily localized to urinary tract.