An Erie County, N.Y., election official was hired by the District of Columbia Board of Elections and Ethics yesterday to take over Washington's troubled elections system.

Teddy Filosofos, Democratic deputy elections commissioner in Erie County and Buffalo, was chosen over about 50 other applicants for the $50,112-a-year job as executive director of the city's elections board.

In that job, Filosofos faces what he described as the "huge problem" of gaining control of the city's chaotic voter registration system, which has been plagued with mistakes that disrupted last fall's elections and threaten to interfere with voting in the September primaries.

The board has not had an executive director since 1977, when it reorganized its operations and forced out former executive director Norval Perkins, whose duties were divided among two other staff members.

Yesterday Albert J. Beveridge III, chairman of the Board of Elections and Ethics, introduced Filosofos at a District Building press conference as "an experienced elections administrator" and the "no nonsense" supervisor whom the board has been looking for since January.

"The people I am leaving in Buffalo do say I am an SOB," Filosofos said at the news conference. "My attitude is we should do it right the first time."

The 54-year-old auto plant foreman has held the Erie County elections post for five years. Previously, he served two years as a deputy county clerk of Erie, supervising 135 employes and preparing a $20 million county budget. He has been on leave since 1975 from his job as a Chevrolet plant foreman in Tonawanda, N.Y., a suburb of Buffalo.

Beveridge said about half of the applicants for the elections post were from the District but that none of them had sufficient experience running elections.

Filosofos' first task will be to work with Geico, the insurance company, which volunteered earlier this year to help straighten out the District's voting registration records.

Board officials have acknowledged that they do not have an accurate list of voters registered in the District, and a City Council committee earlier this year said as many as 50,000 people could have trouble voting this September because of inaccurate, missing or incomplete voting records.

Beveridge said Geico hopes to have a corrected list of voters by early next month.

"You just don't drop 50,000 names," Filosofos said. "It did happen here and nobody caught it." Filosofos said the District, as the nation's capital, should have "the best elections system in the country."

Filosofos, who will start work May 3, also faces a troubled elections staff of about 20 persons that has been torn by charges of incompetence and has not had a full-time supervisor since last summer.

"It's a huge problem," said Filosofos, when reporters asked him to describe his new duties. He said the elections board had sent him newspaper clippings to describe the problems he would face.

In Erie County, Filosofos has had day-to-day responsibility for overseeing, on behalf of the Democratic Party, an election system involving about 470,000 registered voters, compared to about 280,000 here.

Erie County has 1,100 voting precincts compared to the District's 137, and Filosofos oversaw a $3 million budget there compared to this city's $1.7 million operation.