The IIHF World U20 Championship Division III is played every year among the ice hockey teams under the age of 20 who were placed in Division III in the previous year.

Until 2001 the tournament was known as the D-series.

The IIHF U20 World Championship Division III is an international ice hockey tournament organized by the International Ice Hockey Federation (IIHF) for national under-20 teams. This competition serves as a platform for emerging hockey nations to showcase their talent and compete at a high level, with the goal of earning promotion to higher divisions in future seasons. The tournament features teams from around the world, competing in a round-robin format followed by playoff rounds to determine the champion. Held annually, the IIHF U20 World Champs Div 3 promotes the growth and development of young players and the sport of ice hockey across diverse regions.