 Andrejko played overall 16 games and scored 2 goals for the Czechoslovakia national under-16, under-18 and under-23 team but never played for the first team.He was an assistant coach of the Slovakia U-21 team at the 2000 UEFA European Under-21 Football Championship and the 2000 Summer Olympics alongside Dušan Radolský.He was also a head coach of 1.