At the age of 16 he entered the Rostov Theater Institute (workshop of G. Gurovsky), which he graduated in 1968. Then he was drafted into the army (he served in the ensemble of songs and dances of the North Caucasus region - led the emcee). After the army, he was accepted into the troupe of the Rostov Academic Drama Theater. Gorky. Then he moved to Rostov TYuZ. In 1973 he moved to Moscow. As soon as he appeared at the Gorky film studio, he immediately attracted attention with his textural appearance. Immediately followed by a proposal to star in the musical comedy of Vladimir Gorikker "The Star of the Screen." When the shooting ended, unfortunately, there were no new offers, and George had to temporarily return to Rostov. He did not want to return to the theater and therefore got a job as a TV announcer. In 1975, the actor was invited to the role of Tikhon in the adventure film "Golden River". On the set, he met young Alexander Abdulov, who recommended Martirosyan to the Lenkom Theater in the capital. He worked in Lenkom for several years - from 1975 to 1979. During this period, began to regularly act in films. In the early roles, directors often used external data of the actor - big growth, impressive biceps, impassive face, small curls on a huge head, and therefore he was offered the same type of roles. But filmed a lot and regularly. In parallel with the film career, work continued in the theater. In 1980 he came to the Theater of Satire. For three years, he has played several roles on his stage, among them: Egor (“The Grouse's Nest” by V. Rozov), Vasilkov (“Mad Money” by A. Ostrovsky), Matthew-Moneta (“The Threepenny Opera” by B. Brecht). 1983-1993 worked in the theater. Vl. Mayakovsky. Since 1998, plays in the theater "School of the modern play." Among the best roles are: Shamraev in Chekhov's “The Seagull”, and Count Albafiorita in “The Innkeeper”. Participated in entrepreneurial performances. Thus, in the Entreprize of Alexander Abdulov, Sergei played in the play “Everything passes”, and in the entreprise of the Moscow Guild of Actors of Theater and Cinema - Ralph in “The Contract on Murder” and Alfredo in “Ghosts”. Honored Artist of Russia (2004).