Nocioni's agent -- George Bass -- says the Argentina native is "glad to be back."
Financial terms of the deal were not available, but the Chicago Tribune reported it was for approximately 38 (m) million dollars.
Nocioni was a restricted free agent and had drawn the attention of the Memphis Grizzlies.
The 6-foot-7 forward was originally signed by the Bulls as a free agent in 2004.
Known for his hustle, the 27-year-old Nocioni averaged 14 points and five rebounds during the regular season a year ago. He was limited to 53 games -- however -- because of plantar fasciitis in his right foot.
The Bulls are also reportedly interested in landing a veteran free agent from a group that includes Joe Smith, Mikki Moore and Chris Mihm.