Larsson helped Celtic knock the Catalan giants out of the 2004 UEFA Cup – a year after Martin O'Neill's team lost in the final.
But the former Barcelona striker said the 2-1 Champions League win surpassed that result and claimed it was the greatest win at Parkhead in the club's 125-year history.
"Beating Barcelona with the team they have now has to be the best experience, it beats everything I have been involved in myself.
"But also the way you heard the fans through the television, everyone is raving about the atmosphere. They were fantastic again. It's the best result against any team there at Parkhead because you're playing against the world's best team, and the amount of money they have. Being able to do that is fantastic and to see it shows you anything is possible in football. You might have a great team on paper but you still have to play for it."