Disappointed immigration officials said yesterday that only 6,000 illegal immigrants from the District and Virginia, by far the lowest number in the six major national Immigration and Naturalization Service jurisdictions, have applied for amnesty under the new federal law offering legal status to those who arrived before 1982.

The officials also said that their initial estimates on how many people are eligible nationwide may have been exaggerated and that in the Washington area the majority of illegal aliens may not qualify.

"Our estimates could be wrong because it was just a guess," said Richard L. Kenney, a spokesman for the INS who attended a news conference yesterday at the legalization center in Arlington. The figures "were not based on any reliable data or figures. The illegal community has always been difficult to define."

Estimates on the number of illegal residents in the Washington area range from 80,000 to 200,000. Government and community social workers believe that the majority of them, mostly Salvadorans, came to the area after 1982 because of the war there.

Under the Immigration and Reform Control Act of 1986, signed by President Reagan last November, people who have lived in the United States since Jan. 1, 1982, have a year, beginning May 5, to apply for a temporary work permit and start the process toward permanent residence.

Yesterday's news conference was planned in an attempt "to overcome this supposed feeling of fear that the applicants have" in applying for amnesty, said Robert B. Neptune, INS district director for D.C. and Virginia. (Maryland is in another jurisdiction.) Fourteen recently legalized immigrants were introduced at the conference, though they did not make any statements.

Immigration officials said that, nationwide, 834,849 applications have been accepted, including 307,000 in INS offices in Los Angeles, 54,634 in San Francisco, 42,874 in Chicago, 34,065 in New York and 21,946 in New York City.

Once an application is accepted, illegal immigrants are given a temporary work permit pending final approval of the application, which takes about 90 days. After that they are given a temporary residence card and may then be eligible for permanent residence, and eventually U.S. citizenship.

Immigration officials planned initially to accommodate about 4 million people. They now expect no more than 2 million.

Community groups helping immigrants here through the legalization process said they are not surprised by the low figure announced yesterday.

"It's really a very poor showing," said the Rev. Kevin Farrell, director of Centro Catolico Hispano, a nonprofit social service agency serving the Spanish-speaking community in the District. "The question is not where these people are, the question is how we ever made that estimate" of who would be eligible.

Farrell estimated that 90 percent of the 28,000 Spanish-speaking immigrants whom the group served last year would not qualify for amnesty. "Only one out of seven people who walk through our doors now can apply," he said.

Enid Gonzalez, director of El Rescate Nova, an Arlington-based organization serving Hispanic immigrants, said the complexity of the application form also has deterred many from applying. "Every single application is so complicated and there are so many exceptions," she said.