Abstract: Clinically, obstructive sleep apnea hypopnea syndrom (OSAHS) is a common chronic sleep breathing disorder. A number of studies have confirmed that OSAHS is closely related to hypertension and is one of the independent risk factors for hypertension. The cause of OSAHS-related persistent hypertension is not yet fully clear, but most scholars believe that disorder of sleep structure in OSAHS patients may cause hypoxemia and hypercapnia, which may stimulate the central and peripheral chemoreceptor, excite the sympathetic nervous system, release more norepinephrine, and subsequently increase endothelin levels. Then, dependent vascular endothelial cell release factors reduce, and serious vascular smooth muscle hypertrophy and remodeling occur. Significant blood pressure fluctuations in OSAHS patients may also activate RAAS system and increase inflammatory factors, further leading to vascular endothelial dysfunction. In addition, obesity and genetic factors may also play important roles in the development of OSAHS. OSAHS often causes persistent and refractory hypertension. Poor long-term control of blood pressure may lead to target organ damage.