The Yu Tse-san Incident, also known as Yu Zisan Incident, was a series of political events surrounding the death of Yu Tse-san, the chairman of the Students' Autonomous Association of National Chekiang University (NCKU), when he was imprisoned at the Hangzhou Garrison Headquarters, Hangzhou, China, on 29 October 1947. While the Nationalist government claimed to be suicide as he feared of being convicted as a communist bandit, the death of Yu became a cause célèbre causing nationwide demonstrations in November and December 1947.