Sergey V. Garmonin was born in 1953. He is married, with a son and a daughter.

In 1975 he graduated from the Moscow State Institute for Foreign Relations and in 1990 - from the Diplomatic Academy of the Ministry of Foreign Affairs of the USSR.

He is fluent in English, German and Burmese.

In 2000 Sergey V. Garmonin was given diplomatic rank of the Minister Extraordinary and Plenipotentiary 1st class.

He has served several tours of duty abroad:
In 1975-1980 and 1984-1988 he served at the Embassy of the USSR to Burma (nowadays Myanmar);
In 1990-1993 he served at the Embassy of the USSR, later Embassy of the Russian Federation, to New Zealand;
In 1996-2000 he served at the Embassy of the Russian Federation to the Republic of Turkey in capacity of a Minister-Counselor/Deputy Chief of Mission.
In 2001-2004 he was Deputy Director of the Consular Service Department, Ministry of Foreign Affairs of the Russian Federation, having been responsible for consular relations with European countries.

Sergey V. Garmonin many times took part in international conferences on diverse matters as a member of official governmental delegations, he was head of Russian interministerial delegations at negotiations on reaching intergovernmental agreements on consular issues with Lithuania, Poland, Romania, Bulgaria, Latvia, France, Italy, and other countries.

On July 22, 2004 Sergey V. Garmonin was posted as Consul General of the Russian Federation in New York, USA.