The 31-year-old prop was sacked in October 2012 after a photo of teammate Scott Moore's bottom had appeared on his Twitter account.
The picture, which was taken during a drunken end-of-season celebration, was found on Mason's iPhone by girlfriend Lauren Harwood.
She then posted it on his Twitter account alongside the message "what the hell is this?"
The tweet remained on Mason's account for around two days before he found it and deleted it, the court heard.
Huddersfield had claimed that Mason had committed gross misconduct by not deleting the tweet quickly enough.
Mason, who now plays for Castleford Tigers, will receive around £167,000 in damages from Huddersfield, who ended his £95,000-a-year contract with three years left to run.