Zhaozhou Congshen (趙州從諗) (778?-897?), known as Chao-chou Ts'ung-shen in Wade-Giles and Jōshū Jūshin in Japanese, was one of the great Chan (Zen) masters of ancient China.

Zhaozhou took his monastic name from the name of the small town near Beijing where he lived. He is said to have been born in 778 and to have died in 897, giving him an unlikely life span of 119 years. According to the same sources, he only entered monastery life at the ripe age of 61 (or 80), but under the tutelage of Nanquan (Nansen) he learned rapidly and eventually became abbot, a position he held for 40 years. He was known for his asceticism but also his kindness: no sharp raps of the stick for his students, just simple actions and language without a single Buddhist cliche.

Even during his lifetime his fame grew rapidly: five of the 48 koans in The Gateless Gate are attributed to Joshu, as well as twelve of the 100 in the Blue Cliff Record. Probably the best known of these is Zhaozhou's Dog, in which a monk asks the question: "Does a dog have Buddha nature or not?" Zhaozhou famously answered "wú" (無; transliterated into Japanese as "mu").