Klausenburg, also known as Sanz-Klausenburg, is a Hasidic dynasty that originated in the Transylvanian city of Cluj-Napoca (formerly Klausenburg), Romania.

The Sanz (or Tsanz) Hasidic dynasty was founded by Rabbi Chaim Halberstam (1793–1876) who was the rabbi of Nowy Sącz (Sanz, Yiddish: צאנז Tsanz‎) and the author of the work Divrei Chaim by which name he is known as well. He was a son-in-law of Rabbi Boruch Frankel Thumim (1760–1828), the rabbi of Lipník nad Bečvou (לייפניק Leipnik) and author of the work Boruch Taam.

At the behest of Rabbi Yekusiel Yehudah Halberstam, Klausenburger Rebbe from 1927–1994, the movement was split into two separate movements after his death, headed by his two sons. The Sanz-Klausenburger Hasidim are located in Borough Park, New York, while the Sanzer Hasidim are based in Kiryat Sanz, Netanya, Israel. There are also modest followings in Jerusalem, Stamford Hill, Antwerp and Union City, New Jersey.