Petrosyan was born in 1955 in the village of Khnatsakh in what was then Askeran district of the Nagorno-Karabakh Autonomous Oblast.
[1][2] Petrosyan started his career at Armenia's State Museum of Ethnography as chief of the Paleoanthropology Department.
Since 1981, he has been a senior research fellow at the Institute of Archaeology and Ethnography of Armenia's Academy of Sciences.
[1] Petrosyan has led excavations in Shushi, Handaberd, and most notably, the ancient site of Tigranakert in Artsakh.
[1][3][4] He has described Tigranakert as “the best-preserved city of the Hellenistic and Armenian civilizations.”[5] Patrosyan's English publications include:[6]