The former Derby man scored five times in 33 appearances for the Tykes last term and is now committed to David Flitcroft's side for the forthcoming campaign.
"I'm happy to have signed," he told Barnsley's official website, before going on to reveal how he revelled in the successful fight for survival at Oakwell last season.
"The second half of last season showed just what we are capable of and I'm looking forward to the new season.
"The way we played when David took over, especially against the top sides and the quality we showed was the major factor in me wanting to stay here.
"I've never been part of something as crazy and special as what I experienced last season and especially the last game which gave a special feeling to what we accomplished.
"I will be looking to improve as a player this season and I will doing my best on the training ground and for the team on the pitch.
"Most of the players from last season have stayed and we will be looking to start this season off in the way we played the second half of last season."
Flitcroft added: "I am delighted to have added Tomasz to the squad for the new season. We got him late on in our pre-season last year so it will be good to have him at the start of this one.
"He knows us and we know him and he knows what we need and what the fans want. He probably didn't get as many games as he would have liked last season because we had to change our system, but he is a model professional. His conduct is impeccable and his support to the group is unbelievable."