The 27-year-old has joined Schalke on a free transfer as his contract with Leverkusen had expires.
Barnetta has signed a contract that will keep him at Schalke until the summer of 2015.
“We’re delighted Tranquillo has opted to join us,” said general manager Horst Heldt.
“He has great qualities and is very versatile, as he has shown for both Leverkusen and Switzerland.”
