Filatov has played extensively for Russia's national teams in under-18 and under-20 tournaments. His first IIHF competition for Russia was the 2007 U18 Championship held in Finland. Russia won a gold medal in that tournament, and as an underaged player, Filatov contributed four goals and five assists in seven games. He led the Russian team in total points and was second to Alexei Cherepanov in goals scored. After this tournament, Russia's coaches named Filatov as one of the team's three best players. Filatov also played at the 2008 U18 Championship held in his native Russia. Filatov captained the team to a silver medal, scoring three goals and adding six assists. He was named to the Tournament All-Star Team.