Man United boss Ralf Rangnick in the updated list removed Amad Diallo, Donny van de Beek and Anthony Martial from the squad.
The manager also made some changes, bringing in the likes of fourth choice goalkeeper Lee Grant and centre back Phil Jones.
UEFA permits clubs to make up to three changes to their squad after the January transfer window.
The Red Devils removed three senior team players and added Grant and Jones, who have featured twice since returning from injury.
Amad joined Rangers on loan for the second half of the season while Van de Beek followed the same steps to Everton.
Anthony Martial also left the club on loan to Sevilla.
Manchester United had to submit their ‘List A’ players to UEFA by 11pm on February 1, but can still add List B players, who are those under the age of 21, before each matchday.
United will play Atletico Madrid for the first leg on Wednesday, February 23 before the return at Old Trafford on Tuesday, March 15.
United’s 2021/22 Champions League squad:
Goalkeepers: De Gea, Henderson, Heaton, Grant, Kovar (B)
Defenders: Lindelof, Bailly, Jones, Maguire, Varane, Dalot, Shaw, Telles, Wan-Bissaka, Mengi (B), Hardley (B)
Midfielders: Pogba, Mata, Lingard, Fred, Fernandes, Sancho, Matic, McTominay, Mejbri (B), Wellens (B), Savage (B), Iqbal (B), Mather (B)
Forwards: Ronaldo, Rashford, Greenwood (B), Cavani, Elanga (B), Shoretire (B