Leaders of the nation's Indian tribes have voted to reject the proposals of a presidential commission to scale back the federal role on Indian reservations.

Yesterday, the tribal chiefs also sent Reagan a telegram asking him to hold a special "summit conference" with the tribes to discuss the proposals, which would abolish the Interior Department's Bureau of Indian Affairs and give tribes "block grants" and allow them to contract out for the diverse services now provided by the BIA.

Meeting last week in Reno, Nev., members of the National Tribal Chairmen's Association, which represents the leaders of the federally recognized tribal governments, formed a commission to come up with alternatives to the Reagan commission's proposals.

Those proposals, listed in the November report of the President's Commission on Indian Reservation Economies, provoked criticism from the Indians, who fear that Reagan's brand of "less government" will lead to the government severing its ties to the tribes.

The White House has not commented on the proposals officially, and the Interior Department is studying them before making recommendations. But a spokesman there said last week that the opinion of the chiefs would "certainly be a factor" in any decision.