The team officially unveiled the power forward, who won two NBA titles during his time with the Los Angeles Lakers, at a press conference, alongside Nikola Mirotic, who also joins the side as a free agent.
The Spaniard told reporters: "It was a gut feeling. I thought Chicago was going to be the best fit for me. It's a great challenge, but I'm driven by challenge. I look forward to it.
"Their passion, their hunger as well. They're hungry. They're hungry to win, that's something that I wanted to also come into, to be a part of a hungry team.
"How humble they were, I think that's real important to be able to not have big egos, that makes things a lot easier."
Gasol is preparing for his 14th season in the NBA having been drafted by the Atlanta Hawks in 2001.