The 2009 UEFA European Under-21 Championship began on 15 June 2009, and was the 17th UEFA European Under-21 Championship. This was the first tournament after the competition reverted to a two-year format, following the single-year 2006–07 competition, which allowed the change to odd-numbered years. Sweden hosted the final tournament in June 2009; therefore, their under-21 team qualified automatically. Players born on or after 1 January 1986 were eligible to play in this competition.

The UEFA European Under-21 Championship, the UEFA Under-21 Championship or simply the Euro Under-21, is a biennial football competition contested by the European men's under-21 national teams of the UEFA member associations. Since 1992, the competition also serves as the UEFA qualification tournament for the Summer Olympics.