Though it is accepted that the use of positive pressure devices would be the treatment of choice in patients with severe OSA, there is still no concluding evidence of its long-term benefits. These recommendations provided by experts are even weaker when it refers to patients with less severe stages of this pathology. Few are the studies found on the ambulatory use of BiPAP in patients with this pathology. In addition, the studies assessed show poor methodologic quality and scarce number of patients.. The benefits of CPAP are clearly stated, however, the usefulness of BiPAP in this type of patients is not adequately documented. Some health coverages consider it as an alternative when there is not good adherence to CPAP, when concomitant hypoventilation coexists or when desaturation episodes persist despite an adequate adherence to CPAP. However, evidence related to these indications is still limited.