The 2009 IIHF World U18 Championship Division I was an international under-18 ice hockey competition organised by the International Ice Hockey Federation.

Both Division I tournaments made up the second level of the 2009 IIHF World U18 Championships.

Belarus and Latvia won the Group A and B tournaments respectively and gained promotion to the Top Division of the 2010 IIHF World U18 Championships.

The Group A tournament was played in Minsk, Belarus at the Ice Palace from 6 to 12 April 2009.

The Group B tournament was played in Asiago, Italy at PalaOdegar from 29 March to 4 April 2009.