Former Office of Management and Budget director Bert Lance, under fire for new allegations of banking irregularities, has resigned as Georgia Democratic Party chairman, saying he doesn't want his latest fight to become the party's.

"I leave . . . because I desire to regain my status as a private citizen and not because I have done anything improper," Lance wrote in a Wednesday letter to members of the party's executive committee.

"I have worked hard over the past many years as a public figure . . . . I am ready to let others do the job," added Lance, whose chairmanship of the Calhoun First National Bank is the subject of a U.S. probe.

"Also, if I have to fight the OCC Office of the Comptroller of the Currency over the coming months, to stop their abuse and harassment, then that should be my fight and not the party's," Lance wrote.

Lance's resignation comes 11 months after he quit under pressure as general chairman of Walter F. Mondale's presidential campaign and likely marks the end of a political comeback that was built on the power base Lance created from the Georgia party chairmanship.

"I think Bert did a very good job as chairman," Atlanta Mayor Andrew Young said, "but I accepted his reasons. He put in a lot of time during this last presidential campaign; even if it hadn't been for this controversy, he probably needed to give more time to his family and personal affairs."

Terrence B. Adamson, former president Jimmy Carter's lawyer and spokesman, said Lance had "done a superlative job . . . But with the investigation unresolved, "he was going to continue to be a lightning rod for other people using him as a scapegoat for fundamental problems."

Calling Lance "a good guy and a real genius in many ways," State Sen. Julian Bond of Atlanta said he was "sorry the party won't have his talent. But it was clear he needed to step aside . . . . "

"I'm sorry it's happened," said Maxine Goldstein, vice chairman of the state party. "He's done a lot of good for the Democratic Party."

Lance could not be reached for comment.

Lance quit as party chairman amid allegations of "suspected check-kiting schemes and other suspicious transactions" contained in a federal bank-examiner's report.

The findings of the eight-month investigation were revealed in a story published in The Atlanta Constitution June 28. Lance, contesting the findings of the examination, tried but failed to gain a court order to prevent publication of the story.

The report by National Bank Examiner Lloyd R. Elkledge and a cover letter from Robert R. Klinzing, southeastern district administrator for the comptroller's office, both said Lance had engaged in "numerous violations of law" as chairman of Calhoun First National Bank, according to The Associated Press.

In 1977, Lance resigned under pressure as President Carter's budget director, after allegations that he had violated Georgia banking laws. In 1981, Lance was acquitted on all but three counts of a bank-fraud indictment. The jury deadlocked on those three but the government decided not to retry them.

After that, Lance began a political and personal comeback that appeared to reach its peak almost precisely a year ago. On the eve of the Democratic National Convention, Mondale, his grip firmly on the Democratic presidential nomination, decided to dump Democratic National Chairman Charles T. Manatt and replace him with Lance.

But the move, which came as Democrats gathered in San Francisco, caused protest and threatened to ruin the convention for Mondale and his new vice-presidential choice, Geraldine A. Ferraro.

Mondale backed off and decided to keep Manatt as party chairman. But Mondale gave Lance the largely ceremonial post of general chairman of the Mondale-Ferraro campaign, hoping that would satisfy both Lance and his critics.

It did not. Democrats from around the country protested Lance's appointment, making it clear that his controversial background made him unacceptable for such a high position in the Democratic presidential campaign effort.

In early August, after a number of tense days inside the campaign, Lance resigned, under pressure, saying he had become "a source of diversion" for the campaign.

Still, he remained as Georgia Democratic Party chairman.

When the latest allegations of banking irregularities came to light, other Democratic Party leaders in Georgia said Lance should consider resigning, rather than embroil the party in controversy as it prepares for the 1986 elections. The Democrats hope to unseat freshman Sen. Mack Mack Mattingly (R-Ga.).