At the international level, he represents Greece U19. He plays primarily as a Forward.

His most recent move was a from PEC Zwolle U21 to Feyenoord U21 on 2025-06-30.

In the UEFA European U19 Football Championship 2024-2025 season, theodoros delianidis scored 0 goals and provided 0 assists across 3 appearances, averaging 0 goals per game with 0 shots attempted and 0 on target.