The go-ahead was given after Clydesdale Bank agreed funding for building work on the scheme which has a total development value of £80m
The balance of the funding is coming from corporate investors and around 100 doctors who are backing the project with their own cash.
Laing O’Rourke was believed to be originally interested in part-funding and building the hospital but Vinci has now been confirmed as main contractor.
The new Kent Institute of Medicine and Surgery (KIMS) will be built on a seven acre site close to the M20 near Maidstone.
Construction is due to be completed by early 2014.
Paul Abrahams, Vinci Major Project Director, said: “It is fantastic news to have reached financial close on this project and we are looking forward to being able to begin construction on what will be a real asset for the Kent region.
“Our expertise within the healthcare sector and in complex builds makes us well placed to deliver the hospital whilst providing the highest quality modern facilities.”
The design of the hospital includes integrated green roofs and wall, which will improve the external views of the hospital as well as the outlook of those staying in the facility.
In addition, the design of the site includes a large amount of landscaping which will not only enhance the atmosphere for patients, but will be sympathetic to the natural environment.
Vinci will also create a complex road system around the facility to ensure easy access to all parts of the hospital, as well as placing a new roundabout to the south of the hospital to improve existing access.