The Social Democratic Youth movement of Denmark was established in 1920 after a break-up of the former youth organisation, the Social Democratic Youth League (Danish: Socialdemokratisk Ungdomsforbund (SUF)). At first, the organisation was known as the "DsU" (not to be confused with the ).
The founders of DSU wanted to change the Danish society by reforms and not by revolution.
The incumbent chairman of DSU is Peter Hummelgaard Thomsen who was elected at the DSU 2008 congress in April. The general secretary of the DSU is Louise Juul Jensen who was elected at the 2008 congress too. Both were re-elected at the 2010 congress.