The school announced the move Saturday.
Brown led the Longhorns to the 2005 national championship and ranks second at the school in career victories. He's stepping down after 16 seasons - and one tumultuous week of reports and speculation that this was coming.
He is 158-47 at Texas, but 30-20 the last four seasons, including 19-17 in the Big 12.
The 62-year-old Brown was hired at Texas from North Carolina in 1997 and was credited with reviving a dormant program. Texas had a run of dominance from 2001-2009 when the Longhorns went 101-16. He is one of the highest-paid coaches in the country at $5.4 million this year.