The 31-year-old, who won stage 18 of the Vuelta a Espana to take his career total of stage wins in Grand Tours to 11, has signed a two-year deal.
"I see Daniele as a great asset for our team. He is experienced and strong and can prevail in both tougher one-day-races and stage races. He showed in this year's Vuelta he is capable of sprinting with the best and still get results on his own," team owner Bjarne Riis said.
Bennati is also looking forward to the new challenge.
"It's a dream come true for me to be able to ride for at team like Saxo Bank-Tinkoff Bank," he said.
"2013 will be a very important year, I would say it's the start of my 'new' career after a tough season, where I couldn't deliver as usual due to some health issues.
"I'm an experienced rider, and I'm convinced I still have a lot to give to a team like Saxo Bank-Tinkoff Bank, to myself and to cycling in general. I can't wait to start this new experience," he added.