It is one of five changes coach Jamie Joseph has made to the starting line-up for the game at the Sydney Football Stadium in a bid to keep the Highlanders' faint play-off chances alive.
It is a must-win game and Joseph will be relying on Brown's vast experience to get a win.
Brown (36) played 83 games for the Highlanders between 1996 and 2004 and scored 817 points.
He kept in touch with Super rugby by playing for the Sharks and the Stormers and answered an SOS to come back to the Highlanders this year when Colin Slade was injured.
Brown had a starting spot against the Crusaders and played a key role in the upset 26-18 win at Nelson.
But he suffered a knee injury when the Highlanders lost to the Blues 15-10 at Carisbrook on April 29 and has not played since.
Brown replaces Lima Sopoaga, who is representing New Zealand at the junior world championship in Italy.
All Blacks halfback Jimmy Cowan has been dropped to the bench in one of four other changes to the Highlanders' starting team.
Cowan makes way for young halfback Aaron Smith, who has impressed with his swift passing in the games he has played for the Highlanders.
In the forwards, Jason Rutledge replaces Mo Schwalger at hooker and prop Bronson Murray joins Rutledge in the front row, with Chris King moving to the bench.
Alando Soakai comes back at openside flanker in place of John Hardie, who will be on the bench.
After back-to-back home losses to the Lions and the Force, both teams well below them on the table, coach Jamie Joseph's eighth-placed Highlanders must beat the Waratahs and win their final match, away to the Blues next week, to have any chance of making the top six for the playoffs.
Highlanders team to play the Waratahs:
Ben Smith, Kade Poki, Kendrick Lynn, Shaun Treeby, Siale Piutau, Tony Brown, Aaron Smith, Nasi Manu, Alando Soakai, Adam Thomson, Josh Bekhuis, Jarrad Hoeata, Bronson Murray, Jason Rutledge, Jamie Mackintosh (captain). Reserves: Mo Schwalger, Chris King, Nick Crosswell, John Hardie, Jimmy Cowan, Robbie Robinson, Telusa Veainu.
