Trends of College Students' Mental Health from 2005 to 2019 and Its Rural-Urban Disparities in China.

• Mental health worsened from 2005 to 2019 among Chinese college students. • College students from rural areas had worse mental health than those from urban and town areas. • Some aspects of mental health deteriorated more rapidly among college students from urban areas than those from towns or rural areas. • This research has implications for public health and school mental health applications.