Gasan Jōseki (峨山韶碩 1275–23 November 1366) was a Japanese Soto Zen monk. He was a disciple of Keizan Jokin, and his students included Bassui Tokushō, Taigen Sōshin, Tsūgen Jakurei, Mutan Sokan, Daisetsu Sōrei, and Jippō Ryōshū.

Later, he was designated the 2nd head of Sojiji Temple.