Anak the Parthian (Old Armenian: Անակ Պարթեւ, romanized: Anak Part῾ew; fl. third century) was a Parthian noble who, according to the Armenian tradition, was the father of Gregory the Illuminator, who converted Armenia to Christianity in the early fourth century. Anak is said to have killed King Khosrov of Armenia at the incitement of the Sasanians, leading to his own murder and the extermination of his family, except for the child Gregory, who was saved and taken to Roman territory. The details and historicity of this account have been debated by historians.