Objective This systematic review and meta-analysis was performed to evaluate the efficacy of using a helmet for oxygen therapy in critically ill patients with respiratory failure. Methods The Cochrane Library, Embase, and PubMed databases were searched for all randomized controlled trials (RCTs) examining the efficacy of a helmet versus standard oxygen therapy or a mask in critically ill patients with respiratory failure. The quality of all included studies was evaluated by the method recommended by The Cochrane Collaboration. The systematic review and meta-analysis was conducted using Review Manager software, version 5.3 (Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark). Results Ten RCTs involving 708 patients were included in the present meta-analysis. The results of the meta-analysis showed that the oxygenation index, partial pressure of carbon dioxide, and complications were not significantly different between the helmet group and the standard oxygen therapy or mask group. The incidence of intubation and the mortality rate were significantly lower in the helmet group than in the standard oxygen therapy or mask group. Conclusion Delivering oxygen via a helmet can decrease the incidence of required intubation and improve the mortality rate, resulting in beneficial outcomes in critically ill patients with respiratory failure.