AC Milan won all their Champions League Group games in 1992-93 season, they beat IFK Göteborg 4-0 in their first group game then they beat Porto 1-0 and they also beat PSV 2-0 at home. In the reverse fixtures, Milan beat IFK Göteborg 0-1 in Sweden. Milan then travelled to Porto to face the Portuguese side, and beat them 0-1. In their final game of the group stage, Milan travelled to Netherlands and beat PSV 1-2.
PSG beat Bayern Munich, Spartak Moscow and Dynamo Kyiv in Champions League Group stage, at home. In the reverse fixtures, PSG beat Bayern Munich 0-1 in germany and then they travelled to Russia to face Spartak Moscow and beat them 1-2 in a close game. PSG then beat Ukrainian side Dynamo Kyiv in their final group stage game.
Spartak Moscow won all of their Champions League group stage games in 1995-96 season, they beat teams likes Legia Warsaw from Poland, Rosenborg from Norwegian league and Blackburn Rovers from English Premier League. They are the Russian side to win all the group stage games in Champions League
Barcelona are the first Spanish team to win all of their Champions League Group stage games, they beat the likes of Lokomotiv Moscow from Russia, Club Brugge from Belgium and Galatasaray from Turkey. Barcelona won both home and away games in the group stage but lost to Juventus in the quarter final game.
Real Madrid are the second Spanish team to win all of their Champions League Group games and are the only team win all of their group games twice. In 2011-12 Real Madrid beat Lyon from French League, Ajax from Dutch League and Dinamo Zagreb from Croatian League both home and away. Real Madrid again won all of their group games in 2014-15 season, they beat European clubs like Basel, Liverpool and Ludogorets Razgrad both home and away in the group games and lost to Juventus in the semi final game.