The striker has signed a three-year deal with the Cherries, having left Sunderland on a free transfer following the club's relegation from the Premier League.
Defoe, who had a successful loan spell at Bournemouth early in his career, revealed he was joining Eddie Howe's side earlier this month.
He has now penned a deal which is reported to be worth around £65,000-a-week.
The 34-year-old has been in impressive form for Sunderland since his arrival in January 2015, despite their struggles.
He has netted 15 Premier League goals in each of his last two seasons and has earned a recall to the England squad.