Bipolar disorder（ BD） is one of the most common mental disorders and a major cause of the burden of mental illness and disability worldwide. Obstructive sleep apnea syndrome（ OSAS） is a common sleepdisordered breathing. The two are often comorbid and have a close interaction， which not only exacerbates the severity of the disease， but also increases the difficulty of treatment. However， research is still ongoing regarding the mechanism of comorbidity between the two， clinical implications caused by comorbidities， and diagnostic and treatment strategies. This paper reviews four key aspects of the comorbid BD and OSAS： epidemiology， potential pathophysiology， implications of comorbidities， and treatment， with the aim of enhancing clinical awareness of this comorbidity， facilitating early identification and timely intervention， and ultimately improving patient prognosis.