The Social Media survey of marketing professionals by McCann Erickson Bristol found that 86% of them thought social media is more than just a fad.
However, 65.6% of them said they did not know how to use it for the purposes of marketing.
Facebook, Twitter and LinkedIn remain the most popular social networking sites for marketers, with 72.8%, 42.4% and 40.2% having a presence on them respectively.
Around half of those surveyed said their IT departments blocked access to popular social networking sites like Twitter and Facebook -- effectively stopping marketers monitoring what is happening with their brands.
Just over half of UK businesses using social media used them for profile raising or PR, followed by 48% for networking and 30% for advertising.
Joanna Randall head of PR at McCann Erickson Bristol, said: "This study highlights that some of the UK's major businesses are ignoring social media channels -- but they do so at their peril.
"Word of mouth is now more powerful than ever -- opinions can be shared with a global audience at the click of a button.
"We all have the ability to influence, both positively and negatively, and therefore as marketing professionals we should be considering how best to harness the power of social media."