Mdluli, who was formerly known as Gumbi, joined the Buccaneers in 2007 and made 41 appearances for the club.
But the technical team decided not to renew the 30-year-old midfielder's contract 'as niggling injuries have hampered his progress', according to the club's website.
Mkhwanazi rose to prominence under Owen da Gama in the 2007/8 season but following 'The Rubber Doll's' departure, the midfielder's career stalled.
The 25-year-old spent last season on loan with Thanda Royal Zulu and has now been deemed to be surplus to requirements at Parktown.
Bucs have also released Thulani Maseko (22) and Thulani Lukhele (21) who had loan spells at African Warriors last term.