Clear rhinorrhea is a common symptom in patients with obstructive sleep apnea (OSA) and may worsen with continuous positive airway pressure therapy. Clear rhinorrhea can also be the presenting symptom of cerebrospinal fluid (CSF) leak, which is evidence of a communication between the subarachnoid space and the nasal cavity or sinuses. While CSF leak has been reported to occur with nasal continuous positive airway pressure (nCPAP) therapy following trauma to the skull base, its association with OSA and nCPAP therapy in the absence of trauma has not been previously described. We report two patients with OSA in whom CSF leak developed following the institution of nCPAP therapy. In one patient, the rhinorrhea was complicated by meningitis. Both patients underwent successful repair of their defects. One patient successfully restarted nCPAP therapy, while the other refused it.