Bethlen is a Hungarian family name, and may refer to:
Bethlen, son of Lőrinc, Hungarian nobleman, ancestor of the Bethlen and Apafi families
András Bethlen (1847–1898), Hungarian aristocrat and served as Minister of Agriculture (1890–1894)
Gabriel Bethlen (1580–1629), prince of Transylvania (1613–1629), duke of Opole (1622–1625) and leader of an anti-Habsburg insurrection
István Bethlen (1874–1946), Hungarian aristocrat and statesman and served as Prime Minister (1921–1931)
János Bethlen (1613–1678)
Farkas Bethlen (1639–1679)
Kata Bethlen (1700–1759) Hungarian aristocrat and author
Bethlen is also the German and Hungarian name for Beclean, a town in Bistriţa-Năsăud County, Romania, while Betlen is the Hungarian and a German name for Beclean, a commune in Braşov County, Romania.
