The 2008 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 2008 IIHF World U18 Championships.

The Czech Republic and Norway won the Group A and B tournaments respectively and gained promotion to the Top Division of the 2009 IIHF World U18 Championships.

The Group A tournament was played in Toruń, Poland, from 2 to 8 April 2008.

The Group B tournament was played in Riga, Latvia, from 2 to 8 April 2008.