"As soon as you walk in through this door you see these great names, these great cars," said the 22-year-old, who arrived at the factory in a £195,000 orange McLaren MP4-12C Spider convertible.
"There is so much history in this team that it makes you feel great. This is a dream come true for myself to be able to drive for such a team."
Perez replaces 2008 world champion Lewis Hamilton, who has moved to Mercedes, alongside 2009 title winner Jenson Button at the British-based team.
He joins a team whose cars - driven over the years by champions such as Ayrton Senna, Alain Prost, Niki Lauda and James Hunt - are on display in a futuristic factory atrium that also has cabinets full of silverware from the team's 182 race wins since 1968.
The Mexican, who failed to score any points in his last six races for mid-table Sauber, recognised they were big shoes to fill but made clear he was aiming for the top right from the start.
"When you come into McLaren this has to be your target," he said when asked about winning the championship. "Otherwise you should not join McLaren because here everybody is working for that goal. So I am coming here to do the same, to work for that goal.
"It's difficult to set a target from the start of the season. To tell you that I will be on pole in Melbourne will be very difficult for me to know," added the youngster, who was greeted by team principal Martin Whitmarsh in front of the world's media.
"First of all we have to go through testing to try to do the maximum we can, Jenson and myself, to have a very competitive car and then I think we can do a very good job in Melbourne."
The season starts in Australia on March 17 with the first pre-season test in Jerez on February 5.
Perez, who can become the first Mexican to win a grand prix since Pedro Rodriguez in Belgium in 1970, promised to give everything for "this great family that is McLaren".
The Mexican will be starting his third season in F1 after two years with Sauber. He finished on the podium three times last year, including as runner-up in Malaysia and Italy.