The England midfielder — who won the Champions League with the Red Devils in 1999 before joining Real Madrid in 2003 — will be on loan at Milan from Los Angeles Galaxy.
Beckham — who will make the move to Italy in January — had previously declared the potential draw with Alex Ferguson's side as his first choice.
He said: "I would really like to face my former team in the next round. Since I left in 2003, I have not returned to play at Old Trafford.
"Seven years have gone by and I would like for that to happen. Me against Manchester, it would be beautiful, wouldn't it?"
Former United team-mate and fellow Champions League winner Teddy Sheringham expects Beckham to be welcomed with open arms when he returns.
He said: "He'll be getting fit for that tie, he will want to play in that and go back to Manchester United, take all the adulation — and turn Manchester United over as well!"
"Without a doubt, he was a top player, an icon, the supporters will love him coming back to say his goodbyes and see him on the pitch."
The exact dates for the last 16 clashes are yet to be decided. The first legs look set to be played on 16/17 and 23/24 February, while the return games are scheduled for 9/10 and 16/17 March.
I'm sorry but your new outfit is gonna get knocked out.
ac milan is so lousy compared to few years ago..and way too old..
yes no more kaka. he is the most important player for milan. the likes of gattuso and pirlo are older, as is dida. ac milan most promising player is the teen pato, but he is not the complete player still raw as a diamond.