The launch event had McLaren's 2008 and 2009 world champions, Lewis Hamilton and Jenson Button, unveiling the first of the road supercar range.
McLaren plans to invest £750m over five years in the venture.
The UK group, best known for its Formula One team, will start production of the "affordable" MP4-12C two-seater at its new £40m Woking facility next year.
The new car will cost about £150,000 and see an annual production of 1,000 vehicles from 2011.
McLaren is hoping to eventually sell 4,000 cars worldwide each year, which is expected to create up to 300 new jobs at the production centre. McLaren boss Ron Dennis, who has an estimated fortune of £87m, described the company's expansion as "good news for UK plc".
The company introduced its first road car, McLaren F1, about 15 years ago, although only 107 actually got built.
