The Project Finance is a specific modality of financing of projects, in which the flow of box of the project constitutes the main source of payment of the service of the debt to the creators and of return to the capital investors. Additionally, the assets of the project -good and rights- can be given in guarantee to the resource suppliers. The use of the Project Finance provides, amongst other benefits, the access to a bigger variety of sources of resources, a bigger financial leverage of the project, and an efficient allocation of risks between the involved parts.On the other hand, it demands a careful financial engineering, to assure the allocation of the risks. This objective work to show reason and as the Project Finance has been used to make possible projects in two sectors of the economy in Brazil: infrastructure of road transport and generation of electric energy. Serving itself of the methodology of case studies they are presented and compared the available sources of resource,the existing risks, the mechanisms of mitigação and allocation of the risks, and the used instruments of guarantee in the estruturação of the Project Finance in the above-mentioned sectors. Also the difficulties of implementation of the Project Finance in the Brazilian context and the adequateness of these sectors to the use of this modality of financing are analyzed.