The Red Devils won the Premier League, FA Cup and famously beat Bayern Munich in the Champions League final 14 years ago.
Redknapp wrote in his column in The Sun: "For me the pick of the Old Trafford bunch would be the team which won the unique Treble of 1999 — the Champions League, the Premier League and the FA Cup.
"I would love to see that team play the current one. If only. Just recalling the teamsheet from that era sends shivers of excitement through you. It's no wonder they scooped the lot.
"Alex Ferguson has produced great team after great team but that one was perfectly balanced."
Sir Alex Ferguson's side can win their 20th league title if they beat Aston Villa in their Premier League clash later today.