"I'm confident that we can achieve success and my aim is to win stages and the green jersey at the Tour de France," he told Sky Sports News.
Team Sky principal Dave Brailsford added: "What excites me is the attitude he brings to the teams he rides for."
One of Cavendish's wingmen, Austrian Bernhard Eisel, will also join Team Sky next season.
Isle of Man rider Cavendish, 26, is rated as one of the greatest sprinters in the sport's history.
He won five stages at this year's Tour de France with HTC-Highroad to take his tally to 20 in total, claiming the prestigious Maillot Vert - awarded to the best sprinter -for the first time in his career.
Then in September, Cavendish became Britain's first male world road race champion for 46 years when his eight-man GB team helped him to victory over the 266km course in Denmark.
Cavendish has also secured a further 10 Grand Tour stage victories in his career, as well as the overall points title at the 2010 Vuelta a Espana.
Wins gold in the madison at the track cycling world championships in Los Angeles in March 2005
Secures Melbourne Commonwealth Games scratch gold medal for the Isle of Man in March 2006
Takes madison gold in track cycling world championships in Manchester alongside Bradley Wiggins in March 2008
In July 2008, he wins four stages of the Tour de France but, a month later, fails to win an Olympic medal
Becomes only the second Briton after Robert Millar to win stages in all three grand tours after success on stage 12 of Vuelta a Espana in September 2010
Awarded MBE in Queen's Birthday Honours in June 2011
Wins final stage in Paris to make certain of the green jersey at 2011 Tour de France and take total stage victories tally to 20
In September, wins gold medal at the Road World Championships
His future had been subject of speculation since August when HTC-Highroad stated that it would fold at the end of the 2011 season after failing to find a sponsor.
Team Sky's lead rider
hailed his compatriot's decision to join the Manchester-based outfit.
"I think I speak for everyone in the squad when I say that we're all delighted to have Cav joining us at Team Sky," he added.
"He is the best sprinter in the world and has an energy and passion for cycling that is infectious. We have enjoyed a fantastic second season and Mark's signing is another statement of our intent for next year and beyond."
said Cavendish will enjoy a smooth transfer.
"In many ways it's like he's coming home - the team has a number of riders and support staff that he grew up with and it won't take him any time to settle in," said Thomas.
"I think everyone saw that when we helped him to victory for Great Britain at the Worlds, and we are all looking forward to helping him deliver more wins for Team Sky."
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