Oxygen therapy, which is ordered frequently for patients with chronic pulmonary disease, remains a cornerstone of modern medical practice. This study was conducted to compare the efficiency and comfort of a binasal cannula versus a face mask during oxygen therapy. Sixty hypoxemic patients participated in this randomized controlled study. While each patient was hypoxemic, arterial blood gas analysis was performed before oxygen supplementation was begun. Arterial oxygen saturation was continuously monitored during oxygen therapy with a face mask or a binasal cannula. Subjects were allowed to return to their oxygen saturation level in room air before the device for oxygen treatment was changed. The same procedure was then repeated with the other device. Patient comfort was evaluated through the use of a questionnaire that was completed after each treatment period. The mean age+/-standard deviation was 62+/-13 y. No statistically significant difference was noted in oxygen saturation levels achieved with the 2 devices. The binasal cannula reached target oxygen levels (P=.007) more quickly than the face mask. The binasal cannula was reported to be significantly more comfortable (P=.0001), and had significantly fewer reports of dyspnea and restlessness, and was less of a nuisance (P=.019, P=.0001, and P=.0001, respectively). The binasal cannula was preferred for oxygen therapy by 71% of study patients. Although the efficiency of the 2 devices did not differ remarkably, the binasal cannula was regarded as a more comfortable and time-saving device for delivery of oxygen therapy to hypoxic patients.