D.J. Marshall inspired thousands by taking the practice field late last season after being diagnosed with Hodgkin's lymphoma in 2009 and missed nearly two seasons.
The Jayhawks defensive end left the team in preseason camp.
"D.J. Marshall has decided to end his football career," Kansas coach Turner Gill told reporters after Monday's practice. "He will remain at Kansas as a student, while completing his degree in Africa/Africa-American Studies. [He] remains in remission."
Marshall was expected to compete for playing time on the defensive line this season after being declared cancer-free in November, but he's decided to keep his focus in the classroom.