Drossos Koutsokostas was born in Thessaloniki and began his study of Byzantine music at the age of nine, first with Zacharia Paschalidis and then with Eleftherio Georgiadis. He gave concerts at an early age, both as a solo singer and as a member of the groups Attares, En Chordais, and Traditional Roads. He has also collaborated with many dancing groups in performances throughout Greece.
Koutsokostas has taught traditional singing in the Department of Traditional Music at the Technological Educational Institute of Epirus, as well as in the music school of En Chordais, for which he served as educational director for four years. He has worked with significant musicians of traditional music and he has participated in many recordings of greek folk music in independent labels.