The carmaker, which has lost more than £7.5bn over the past two years, says the new facility is crucial to its future.
Last month it announced it would not meet its longstanding goal of returning to profitability in 2009 and would be forced to make layoffs in the USA.
The new factory, and other changes to Ford's Mexican operations, are likely to create an estimated 4,500 jobs in Mexico, where car workers earn substantially less than their American counterparts.
The factory will build Ford's new Fiesta, which will lead the company's attempt to shift American buyers towards smaller, more fuel-efficient cars.
The plant is expected to start delivering the Fiesta to the US market in 2010.