The 23-year-old United States international signed a four-year deal as he completed his move to the Stadium of Light from Dutch side AZ Alkmaar on Tuesday.
Altidore, who scored once in 28 Premier League appearances for Hull City during a loan spell in 2009/10, will join up with the rest of the Sunderland squad for their pre-season training camp in Italy.
Altidore told the club's official website: "I'm excited.
"Anybody who knows anything about football knows that the Barclays Premier League, when you look at everything as a full package, is the biggest league in the world.
"I'm thrilled to be here and I'm looking forward to getting adjusted as quickly as possible.
"It's a fantastic club, everyone here is so welcoming. I'm really excited about this season - it has everything here, all the combinations to be a big club, so I'm really excited to be a part of it."
Sunderland start the season at home against Fulham on 17 August and Altidore is excited by the prospect of playing in front of the Black Cats fans.
"It's great, it's part of taking that next step as a player," he added. "To be able to play in front of a stadium like that is going to be really exciting - I hope they like what I do on the pitch.
"Everybody, I'm sure, is excited to get the season off to a good start and I'm no different.
"I can't wait to meet the guys, meet the coaching staff and get acclimatised as soon as possible.
"I'm just going to give everything I can to the team, that's the biggest thing, to get the respect of your team-mates and when you do that, I think everything will fall into place."