Leo (or Leon) IV of Armenia (died 1307) was king of the Armenian Kingdom of Cilicia, ruling from 1292 to 1307, along with his uncle Hethum II. He was the son of Thoros III of Armenia.
He was married to his cousin Marie de Lusignan, daughter of Princess Isabella of Armenia and Amalric de Lusignan .
In 1307 Leo and his co-ruler Hethum II were murdered while visiting the Mongol emir Bilarghu at Navarza.