The 2003 IIHF World U18 Championship Division I was a pair of international under-18 ice hockey tournaments run by the International Ice Hockey Federation. The Division I tournaments made up the second level of competition at the 2003 IIHF World U18 Championships. The Group A tournament took place between 23 and 29 March 2003 in Ventspils, Latvia and the Group B tournament took place between 22 and 28 March 2003 in Briançon, France. Denmark and Norway won the Group A and Group B tournaments respectively and gained promotion to the Championship Division for the 2004 IIHF World U18 Championships. While Great Britain finished last in Group A and Ukraine last in Group B and were both relegated to Division II for 2004.