Ferguson saw his side torn apart 3-1 at Wembley as the Catalan club, inspired by the brilliant Lionel Messi, won their fourth European Cup - and third in the past six years.
The best: Lionel Messi roars in triumph as his goal condemns Manchester United to defeat at Wembley
'We were well beaten by a fantastic team, there's no other way to describe it,' said Ferguson, who has managed United since 1986 and was hoping to lift the European Cup for a third time.
'The best team we have ever played. I expected us to do better but we have to acknowledge we were beaten by a better team. No one has given us a hiding like that.'
Down-hearted: Sir Alex Ferguson shows his dejection at the final whistle
Wayne Rooney's 34th-minute equaliser wiped out Pedro's opener but the outstanding Messi restored Barca's lead early in the second half and David Villa killed off United. It must have been as painful for Ferguson and his players as the 2009 final in Rome when Barcelona ran out 2-0 winners against a United side which included Cristiano Ronaldo.
'You get teams who elevate themselves to that status and Barcelona are that team,' added Ferguson.
'They mesmerise you with their passing. We never controlled Messi but many teams over the past couple of seasons could say that. Our challenge now is to get better and better. Next season we may improve even more.'
Ferguson was still very proud of United's campaign, which also saw them land a record 19th English league title.
'It has been a great season in many ways but we are disappointed to lose at Wembley twice, against Barcelona and in the FA Cup semifinal against Manchester City. This is a fantastic stage and we are disappointed it has ended like this.
'There is good evidence we are a consistent European team. Our record has been excellent, we have won important games, but tonight we were beaten by the best team in Europe. There is no shame in that - sometimes you come up against a team that is far better than you, and tonight was that night.'
There is doubt over Paul Scholes' future at United and Ferguson said: 'Paul has not made his mind up yet - we'll talk to him next week.'
But it was definitely the last match in a United jersey for veteran 40-year-old goalkeeper Edwin van der Sar, who now retires.
Plenty to Roo: Wayne Rooney casts an envious glance at Barcelona's celebrations
'Edwin has been a fantastic servant for Manchested United and we wish him well,' added Ferguson. 'He's had a great career with tremendous honour and professionalism. He stands out.'
Van de Sar said: 'They had the better chances and we made one or two mistakes. But they finished (them). They are very good. We started well, the same as in Rome in 2009, and we had to score the first goal but we didn't.'
Meanwhile, Barcelona coach Pep Guardiola scotched rumours that he is prepared to leave the Catalan club, with only one year left on his contract.
Roman Abramovich, the owner of managerless Chelsea is known to be big admirer of the man and his footballing philosophy but Guardiola, 40, insisted he would still be at the Nou Camp next season.
Sealed with a kiss: Pep Guardiola has vowed to stay at Barcelona next season
Guardiola, who played when Barcelona lifted the European Cup for the first time in 1992 at the old Wembley, said: 'We are so happy to win, of course, but (also) we are so, so happy to show to the world our way to play, to keep the ball, to try to attack in front of absolutely one of the best teams of the world.
'Through pass, pass, pass we have won the game. The dream team of 1992 showed us the way to play. '
And he added: 'I have one year left on my contract. Yes, I will be here next year.'
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Explore more:People: Alex Ferguson, Paul Scholes, David Villa, Cristiano Ronaldo, Wayne Rooney, Roman Abramovich, Pep Guardiola, Edwin Van Der Sar, Lionel Messi Places: Barcelona, Rome, Europe