In the early 1930s, state persecution intensified, forcing the KJV to operate under increasingly precarious and often illegal conditions.

They conducted sabotage operations, distributed leaflets denouncing the war and Nazism, and advocated for a free, independent Austria.

Additionally, the organization prioritized advocating for the interests of young workers and vocational students, and it played a key role in peace movement activities.

In response, the organization's name was expanded to "KJÖ-Junge Linke" to reflect its continued aim of building a broad, influential left-wing youth movement by engaging young people with diverse political perspectives.

The KJÖ has been involved in various movements, including protests against the formation of the conservative-right government coalition and opposition to the Iraq War.

In Braunau am Inn, the KJÖ organizes a major anti-fascist protest each year just before Hitler's birthday, supported by Mayor Gerhard Skiba and Green Party National Council member Karl Öllinger.

On February 16, 2007, American celebrity Paris Hilton was in Vienna for an autograph session in a mall when she had to be rushed offstage because members of the Communist Youth began throwing tubes of lipstick and lit cigarettes at her.

In 2018, the founding of the Young Left as the official youth wing of the KPÖ further solidified the KJÖ's separation from the party.

The KJÖ maintains good and friendly relations with the Communist Student Association (KSV) and the KPÖ in Styria.

In Tyrol, during the 2008 state elections, there was an electoral alliance between the KPÖ and the KJÖ, achieving the best result for a communist list since 1956.