Yu competed at the 2021 Chinese Youth Games, finishing ninth with the Shanxi provincial team.[2] At the 2022 Chinese Youth Championships, she finished fourteenth in the all-around in the under-14 group. She qualified for the floor exercise final where she finished seventh.[3] Then at the 2022 Chinese Championships, she finished fourteenth with the Shanxi provincial team and thirty-second in the all-around qualification round.[4]
Yu was selected to compete at the 2023 Junior World Championships alongside Jiang Shuxuan and Qin Xinyi, and the team finished in sixth place.[5] Individually, Yu qualified for the balance beam final in second place behind Japan's Sara Yamaguchi with a score of 13.100.[6] In the event final, she won the gold medal with a score of 13.133.[7] Then at the 2023 Junior Asian Championships in Singapore, Yu helped the Chinese team win the silver medal behind Japan.[8] Individually, she finished ninth in the all-around and seventh in the balance beam event final.[9]