The Ritharrngu (Ritharrŋu, Ritharngu) and also known as the Diakui (and variant spellings), are an Aboriginal Australian people of Arnhem Land in the Northern Territory, of the Yolŋu group of peoples. Their clans are Wagilak and Manggura (of the Dhuwa moiety), and Ritharrŋu (of the Yirritja moiety).