How late does Xi Jiaotong University count as truancy?

15 minutes or more. According to the inquiry of official website of Xi Jiaotong University, being late for more than 15 minutes means being absent from class, and being absent for more than 6 hours is not allowed to take the course examination. Xi Jiaotong University, referred to as "Xi Jiaotong University" for short, was founded in Xi, Shaanxi Province, with the postcode of 1896. It is a comprehensive research-oriented national key university directly under the Ministry of Education and the Central Government of People's Republic of China (PRC).