Purcell will continue to coach at Louisville through the Cardinals' NCAA tournament run.
Nikki McCray-Penson stepped down as Mississippi State coach in October because of health concerns, and Doug Novak filled in as interim head coach as the Bulldogs finished 15-14 (6-10 SEC).
Purcell got into coaching as a student at Auburn in 2000 then had stints as an assistant at Tulsa and Georgia Tech before going to Louisville in 2013. He was part of the Cardinals' 2018 women's Final Four team. This season, Louisville is 25-4 and is projected as a No. 1 seed in the NCAA tournament.
"During our search, Sam Purcell routinely emerged as one of the nation's elite recruiters and more importantly, a terrific fit to lead our program," Mississippi State athletic director John Cohen said in a statement. "Sam has been an integral part of some of the most successful teams in women's basketball. He is creative, meticulous, and has shown a proven ability to recruit the nation's top talent and develop student-athletes."
Mississippi State's peak years came under coach Vic Schaefer, who took over at the school in 2012 and led the Bulldogs to the 2017 and 2018 national championship games. Schaefer left for Texas after the 2019-20 season.
"The Purcell family is thrilled to be coming to Starkville, and we can't wait to meet the team and the entire Bulldog family," Purcell said in a statement. "Mississippi State women's basketball is synonymous with winning, and I fully intend to continue that winning culture."