Obstructive sleep apnea (OSA) and dizziness are common conditions observed in the general population, and several epidemiological studies have reported an association between OSA and dizziness. Vestibular dysfunction, autonomic instability, and cerebellar degeneration secondary to recurrent hypoxia are implicated as mechanisms underlying dizziness in patients with OSA. Moreover, OSA is a risk factor for many diseases associated with dizziness, including Meniere disease, stroke, and psychiatric conditions. A dizziness questionnaire, vestibular function tests, and tests for autonomic function are useful for evaluation of OSA and concomitant dizziness. A growing body of evidence has shown that effective treatment of OSA including continuous positive airway pressure therapy reduces dizziness in these patients. Greater attention to dizziness is warranted in patients with OSA.