Anthony France, 42, had his May 2015 conviction quashed.
"I am delighted that this serious miscarriage of justice has ended today," he said outside court.
He was the only journalist to be successfully tried under Operation Elveden, Scotland Yard's probe into payments to public officials for story tip-offs.
Lady Justice Hallett, who heard the appeal with Justice King and Justice Dove, announced that France's conviction would be quashed and said there would not be a re-trial.
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France was convicted of aiding and abetting PC Timothy Edwards to commit misconduct in public office between March 2008 and July 2011 following a trial at the Old Bailey last year.
PC Edwards sold 38 stories and tip offs to France between March 2008 and July 2011 in exchange for more than 22,000 pounds.
He pleaded guilty to misconduct in a public office and was jailed for two years in 2014.
In a written ruling, Lady Justice Hallett said they concluded that the jury "were not provided with legally adequate directions tailored to the circumstances of the case and that the conviction was unsafe".
"In the course of the last five years, 19 journalists from 'The Sun' were prosecuted as a result of Operation Elveden and not one has resulted in any conviction being upheld," said a spokesperson for News UK, the company which owns the tabloid.