The aboriginal group agreed to back development of the Lower Churchill Project in return for outright title to 5,000 square kilometres (1,931 square miles) of land in the Labrador region of Atlantic Canada, control and use of 22,000 sq. km of provincially owned land, and royalty payments.
The project would see two dams built on the Churchill River, which could generate 2,800 megawatts of power beginning in 2015.
The electricity would be destined for markets in Eastern Canada and the U.S. Northeast.
"This signals an extremely important and significant step on the road to development of the Lower Churchill Project," Newfoundland Premier Danny Williams said in a statement. "Newfoundland and Labrador is substantially closer to finally seeing this project developed."
The Innu will receive 5 percent of the development's net revenue and $5 million annually from the time the development is given the green light until it begins producing power.
The native group will also receive $2 million a year until 2041 in compensation for an existing hydroelectric development on the upper Churchill River.
The agreement needs to be ratified by the Innu people.