Tudgay rejoins the Tykes after spending nearly two months at Oakwell on loan last season, and the former Sheffield Wednesday forward is delighted to be returning to the club.
The 30-year-old told the club's official website: "I jumped at the chance. They're a great set of lads here.
"I always say that given the opportunity, I will score goals. If I can come here, score one or two goals and help the team, then that'll be good."
Tudgay scored three times during his nine-game spell with Barnsley last winter.