西海

西海, meaning "west sea", may refer to:

In the Chinese reading Xīhǎi:
 * Xihai Jun, a prefecture of ancient China
 * Qinghai Lake, one of the Four Seas of China

In the Korean reading Seohae, alternatively spelled Sŏhae:
 * Sohae University (서해대학교/西海大學校) in Gunsan, South Korea
 * Former name of Hwanghae, one of the Eight Provinces of Korea during the Joseon Dynasty
 * The Yellow Sea, sometimes also called the West Sea of Korea

In the Japanese readings Saikai or Nishiumi:
 * Saikaidō, a region of ancient Japan
 * Saikai, Nagasaki (西海市), city in Nagasaki Prefecture
 * Nishiumi, Ehime (西海町), former village in Ehime Prefecture