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. The Group A tournament was played in Minsk, Belarus, and the Group B tournament was played in Asiago, Italy. 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.
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All times are local.
The Group B tournament was played in Asiago, Italy at PalaOdegar from 29 March to 4 April 2009.
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All times are local.