In 1968, Ter-Petrossian graduated from the Oriental Studies Department of the Yerevan State University. In 1972, he completed his postgraduate studies at the Leningrad State University. In 1987, he received his doctoral degree from the same university. In 1972-1978, Ter-Petrossian worked as junior researcher at the Literature Institute of Armenia named after Manouk Abeghian. In 1978-1985, he held the post of science secretary at Matenadaran named after Saint Mesrop Mashtots. Since 1985, Ter-Petrossian has been working at Matenadaran as a senior researcher.