Fields, who is currently attending Trinity Valley Community College, committed to Louisville during his official visit on Sunday. He is ESPN's No. 3-rated junior college recruit.
Fields announced his decision on his Twitter account.
The 6-foot-3, 250-pound Fields earned Big 12 Defensive Player of the Year honors as a true freshman in 2012 and was the league's preseason defensive player of the year in 2014. He was dismissed from TCU last August after being charged with misdemeanor assault in July, stemming from allegations he threatened and hit his ex-girlfriend. His legal process has yet to be resolved.
In his only season at Trinity Valley, Fields recorded 61 tackles and 6.5 sacks and helped lead the program to a 12-0 season.
Fields will sign on Wednesday, enroll this summer and have two seasons of remaining eligibility at Louisville.