The 24-year-old, whose contract runs until the end of the season but carries options, was on trial at the Students after leaving title rivals Mamelodi Sundowns in January.
Wits said on Twitter: "We are pleased to welcome Chris Uzoenyi to the family. Good luck as you add strength to our attacking force."
Uzoenyi will look to revive his career having spent the past two campaigns without game-time at Chloorkop.
The diminutive attacker initially joined the Brazilians in 2014 from Enugu Rangers following a strong showing at the African Nations Championship (CHAN).
The Clever Boys also recently added former Ajax Cape Town captain Granwald Scott to their roster in a bid to dethrone champions Sundowns.