Sergey Sheyko was commissioned into the Naval Infantry in 1989 after completing the Far Eastern Higher Combined Arms Command School.
In January–May 1995 captain Sheyko, commander of marine company, participated in the First Chechen War, including storming of Presidential Palace in Grozny.
He showed outstanding degree of personal courage and military mastership.
In fierce battles his group performed important tasks, with virtually no losses of his subordinates.
Sheyko completed postgraduate military education in the Combined Arms Academy of the Armed Forces of the Russian Federation (2000) and General Staff Academy (2005) and, at 2009, service with the Baltic Fleet naval infantry.