Yu became an early organizer, along with Li Chang, Qian Weichang and Qian Jiaju, of the Chinese National Liberation Vanguard (Minxian) upon the organization's founding in 1936. The organisation emerged in the aftermath of the December 9th Movement. Many of its early advocates nad participants went on to become revolutionary leaders and public officials of the People's Republic of China, including Huang Jing, Yao Yilin, Xiong Xianghui, and Xu Jiatun. The league underwent a period of transition under their leadership, which laid the foundation of the Youth League of the Communist Party.
