Signing Beckham, who has promoted products including Armani underwear, Motorola phones, Sharpie pens and Pepsi, will provide huge commercial benefits for AC Milan, which is itself sponsored by GM-owned car manufacturer Opel.
Adriano Galliani, the president of AC Milan, confirmed that Beckham will join the team in January on loan from LA Galaxy for "a few months".
Galliani said: "Beckham chose Milan. Our team is ultra competitive and will remain so but Beckham is something different and intriguing ... He will bring more fans."
Beckham's temporary move to AC Milan is expected to help him keep his place in the England squad for 2009's World Cup qualifying campaign as England manager Fabio Capello has said that he will not pick players who are inactive.
Beckham's advisors deny that he will not return to LA Galaxy stating that it will be a "short-term loan".
Beckham is under contract with LA Galaxy but their regular season finishes on Sunday. He would have to return to LA when their new season starts in April.
However there is speculation that the move will mark the end of Beckham's career in America.
The other half of Brand Beckham, Victoria or Posh Spice, is expected to remain in LA with their three children, Brooklyn, Romeo and Cru, and fly out in the school holidays.
Beckham's last attempt to work away from home, when he joined Real Madrid in 2003, resulted in problems for the couple's marriage due to allegations of an affair with his former personal assistant Rebecca Loos.
The couple have made a number of celebrity friends since their move to LA including Tom Cruise and Katie Holmes, Will Smith, Eva Longoria and Governor Arnold Schwarzenegger.