Li Siyi graduated from the Affiliated Dance School of Liaoning Ballet in 2018 and entered Liaoning Ballet in the same year. And she entered the National Ballet of China in 2023.

In 2015, she won the gold medal in the junior group of the 11th Fukuoka International Ballet Competition in Japan; In 2016, the ballet Eight Heroines, in which she danced the leading role won the highest government award for Chinese culture and art - “Wenhua Award”; In 2017, she won the gold medal in the junior group of the 1st Ballet Grand Prix Vienna, the silver medal in the junior group of the 13th Moscow International Ballet Competition and the gold medal in the junior group of 10th Korea International Ballet Competition. The ballet Eight Heroines, in which she danced the leading role won the Best Works Award in the 14th Spiritual Civilization Construction; In 2018, she won the gold medal in the junior group of the 28th Varna International Ballet Competition and the best youth award, and the gold medal in the junior group of the 6th Shanghai International Ballet Competition.

She has danced the main roles in many Chinese and foreign ballets as well as classic and modern dance works such as Swan Lake, The Nutcracker, Spartacus, Eight Heroines, and Chinese Mulan.