Brett Graham's two-Michellin-starred eatery, based in Notting Hill, knocked Marcus Wareing at the Berkeley off the top spot for the first time in four years in the 2012 Harden's Guide. However the Berkeley still retained its crown for London's best gastronomic experience.
The Ledbury has shot up the rankings after not even being among the top 20 three years ago.
The results will no doubt give London apartment visitors food for thought when considering where to dine out.
Those wanting to eat with the locals would be best visiting Bruce Poole's Chez Bruce, which retained its title of Londoners' favourite restaurant for the seventh year in a row.
Meanwhile the much-hyped Heston Blumenthal's Dinner at the Mandarin Oriental was named best newcomer, while the Wolseley kept its best for business and breakfast titles.
Those wanting more of a romantic spot will now be heading for Clos Maggiore in Covent Garden after the restaurant knocked Pimlico's Poule au Pot off the top spot after 16 years.
The Harden's Guide is compiled from the findings of a survey of 8,000 restaurant goers.
Brett Graham, 32, said: 'It is a massive honour and privilege to be voted by our customers. That is the most important thing.
'I am really chuffed because three years ago we were not even in the top 20. We don't try to get into guides - the best recognition is we are full every day.'
Peter Harden, co-editor of Harden's London Restaurants 2012 Guide, said: 'Brett Graham and the team at the Ledbury deserve the highest credit for establishing the Ledbury as the restaurant where you find London's best food.
'It is also an extraordinary achievement for Nigel Platts-Martin, who co-owns both Chez Bruce and the Ledbury.'
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