Chile has become the sixth Latin American country this year to reject U.S. financial assistance because of the Carter administration's attempts to use foreign aid as a lever in human rights disputes.

State Department officials confirmed yesterday that they received a diplomatic note formally spurning the proposed $27.5 million economic aid package on Tuesday.

That was the same day that the department announced its intention to hold up $9.3 million of the package for 30 to 60 days to express disapproval of human rights violations by the Chilean government of President Augusto Pinochet.

The Pinochet regime seized power from Marxist President Salvador Allende in a bloody 1973 military coup in which Allende was killed. Since then, thousands of Chilean exiles have accused the regime of systematically killing, imprisoning and torturing persons that it regards as enemies.

Chilean embassy sources said last night that Pinochet's decision to spurn U.S. aid was made before the State Department revealed that the loan for programs to aid Chilean farmers would be held up. By coincidence, the sources added, the Chilean note was delivered almost simultaneously with the department's announcement of the loan delay.

In yet another coincidence, Tuesday also was the day visiting Venezuelan President Carlos Andres Perez lavishly praised President Carter for his strong stance on human rights questions. However, as the Chilean action indicated, there is a wide gulf between the attitudes of Perez, one of Latin America's few democratically elected leaders, and the repressive military regimes that dominate most of that region's countries.

The dispute with Chile marked what State Department sources characterized as the first case of economic aid being withheld for humanitarian reasons.

Earlier this year, though, five other Latin American countries - Brazil, Argentina, Uruguay, Guatemala and El Salvador - rejected U.S. military assistance on the grounds that Washington's pressures over human rights questions were an interference in their internal affairs.

Argentina and Uruguay said they would not accept U.S. aid of any kind. Brazil, traditionally the staunchest U.S. ally in South America, also canceled its 25-year-old military assistance treaty with the United States.

The aid package for Chile, already approved by Congress as part of the fiscal year 1977 budget, included $15 million for surplus wheat sales and $12.5 million for a variety of development loans and grants. These included the blocked loan, which was to finance an irrigation project and other small agricultural development.

State Department sources yesterday denied reports that the loan had caused a controversy between department human rights officials, who wanted it withheld, and officials of the Latin American bureau and the Agency for International Development, who reportedly favored going ahead with the loan.

The sources said there had been much discussion about whether economic assistance intended to help poverty-stricken farmers should be used as a weapon in the human rights debate. In the end, the sources insisted, the diplomatic and AID officials in the Latin American bureau agreed that the loan should be withheld as a gesture of disapproval.

The development loans involved in the dispute are described as the last U.S. aid currently planned for Chile, which formerly was the largest Latin American recipient of U.S. financial assistance. Congress voted last year to limit economic aid to Chile and barred military assistance on human rights grounds.