Underwood began his coaching career as a graduate assistant at Hardin-Simmons during the 1986–87 campaign. He continued his coaching career as the head coach of Dodge City Community College, where he led the Conquistadors to a 62–60 record from 1988 to 1993. In 1993, he joined Jim Kerwin's staff at Western Illinois, with whom he spent 10 years as an assistant. He led Daytona Beach Community College to a 70–24 record from 2003 to 2006 and was twice named the Mid-Florida ConferenceCoach of the year. He served as assistant coach under Bob Huggins and Frank Martin at Kansas State from 2006 to 2012. In 2012, Martin left to become head coach at South Carolina, and Underwood followed him to Columbia as his associate head coach.
Head coaching career
Stephen F. Austin
On April 30, 2013, Underwood was hired as head coach of Stephen F. Austin. He replaced Danny Kaspar, who left after 13 seasons to become the head coach of Texas State. According to athletic directorRobert Hill, "Brad Underwood brings years of experience to SFA and has coached at the highest levels of Division I basketball. All of this plus his knowledge of the game and ability to recruit makes him the perfect hire for our men's basketball program. He has great plans on how we can make this program even better." In his first season at the helm, Stephen F. Austin captured the Southland Conference regular-season championship going a perfect 18–0 in conference play. He was named Southland Coach of the Year. SFA was awarded the Southland Conference automatic berth to the 2014 NCAA Men's Division I Basketball Tournament where they upset VCU in the round of 64, before eventually falling to UCLA. Underwood's third season saw him win the Southland Conference tournament again and an automatic bid to the NCAA Tournament as a 14 seed. He then led the Lumberjacks to an upset victory over the third-seeded West Virginia Mountaineers coached by Bob Huggins, who he worked as an assistant with at Kansas State. Stephen F. Austin had a 75–70 lead over sixth-seeded Notre Dame with two minutes to play in the second round before the Irish scored six straight points and won on a tip-in with 1.2 seconds left.
Oklahoma State
On March 21, 2016, Underwood was hired as head coach of Oklahoma State. He replaced Travis Ford, who was fired after a 12–20 regular-season record. He led the Cowboys to a 20–13 record in his only season as head coach, ending with a loss to Michigan on March 17, 2017, in the NCAA tournament.
Illinois
On March 18, 2017, Underwood was hired as head coach of Illinois, replacing John Groce. Underwood signed a six year contract through 2023 worth $18 million that includes two retention bonuses. On March 2, 2020 it was announced that Underwood and his assistants had received extensions. Underwood's contract was extended until the 2026 season and moves his base salary to $3.4 million, which ranks in the upper quartile of the Big Ten Conference.
Professional players coached
Head coaching record
Junior college
College
Personal
A native of McPherson, Kansas, Underwood attended Kansas State University and lettered on the basketball team between 1984 and 1986. He graduated from Kansas State with a bachelor's degree in radio and television communications in 1986. He is married to Susan Underwood and has three children: Tyler, Katie, and Ashley. Tyler plays for his dad at the University of Illinois.
