Robert Lewandowski: Poland striker completes move from Bayern Munich to Barcelona
The 33-year-old had one year left on his contract with the German champions but in May said: "My story with Bayern is over.".
He has joined his new team-mates in Miami as part of Barcelona's four-match tour in the United States.
"I'm finally here. I'm delighted to be at Barca," Lewandowski said.