Obstructive sleep apnea syndrome (OSAS) and arterial hypertension (HT) are two frequent, often concomitant diseases, who are both associated with an increased cardiovascular risk. In the last years, an association between these two entities has been established. The purpose of this article is to review the current knowledge about the link between HT and OSAS, the pathophysiological mechanisms involved in the common genesis of the two conditions and the characteristics suggesting an underlying OSAS in a hypertensive subject. We will also update readers about the current screening of OSAS in which primary care physicians are directly involved, and review the pros and cons of different treatment options for HT in OSAS.