The LA Galaxy footballer topped the poll launched by Austin Reed to mark its Suit Swap project with mental health charity Mind.
Hollywood icon George Clooney was in second place, while James Bond star Daniel Craig came third.
"Undoubtedly David Beckham is one of the most stylish men to grace the planet," an Austin Reed spokesman said.
"His allure is that he can pull off the casual scruffy look but transforms himself into a dashing gent when he dons a sharp suit.
"Equally George Clooney looks effortlessly debonair on the red carpet when he sports a tailored suit."
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Copyright: PA Images Ian West/PA ArchiveHe added: "A good suit can transform a man. Most men need to wear a suit at some point in their lives and it's important to choose wisely.
"This is an amazing opportunity to get a new suit and give to charity at the same time. It has been terrific to see celebrities getting involved with their donations so we encourage the public to raid their wardrobes and get involved."
For the Suit Swap campaign, people can donate their suits to a Mind charity shop or Austin Reed store in return for a £50 Austin Reed voucher.
Musician and filmmaker Plan B has donated a suit to the campaign and said: "Mental health is a really important issue and the work that Mind does to help people with mental health problems is amazing.
"I'm really pleased to be supporting Mind by donating this suit and I hope that people bid generously for it and raise as much money as possible."