Hagop Terzian (; August 22, 1879 – 1915) was an Armenian writer and pharmacist who lived in the Ottoman Empire. The theme of much of his writings was Armenian life and heritage in the region of Cilicia. He published a five volume eye-witness account of the Adana massacre. This publication was confiscated by Ottoman authorities but has been preserved. The entire work was republished by the Gomidas Institute in 2009. Terzian was arrested on 24 April 1915 at the start of the Armenian genocide, deported and eventually murdered.