Jackson is a guard transferring from Long Beach State, who will become eligible for competition during the 2018-19 season.
"Loren is a terrific fit for how we want to play; he excels off ball screens and in the open court," Groce said. "He is a gifted leader with a high basketball I.Q. He will make an immediate impact on our team and the future success of Zips Basketball."
The Windy City native appeared in 34 games and started five times for the 49ers as a freshman in 2016-17. In 18.9 minutes per game, he averaged 5.8 points, while shooting 43.