The province says the approach will remove costly projects from its books and could be a model for other governments.
The Caisse manages provincial pension funds and is one of Canada's largest investment managers.
It will create a subsidiary that will plan, finance, develop and operate projects that have potential to generate returns for its clients.
The first two projects are a public transit system on Montreal's new Champlain Bridge and transit link between downtown Montreal and Trudeau International Airport on the city's West Island. The Caisse is aiming to complete the projects, worth $5 billion, projects before the end of 2020.
Other projects proposed by the government would be added and financed by equity investment and long-term debt.
The Caisse has more than 15 years of experience in infrastructure investment in Canada, Europe, the United States and Australia. In 2005 it was lead investor in the construction and operation of The Canada Line, the rapid-rail service connecting Vancouver Airport with the city's downtown.