The Justice Department is preparing to close its investigation of former Democratic vice-presidential nominee Geraldine A. Ferraro without seeking an indictment, according to law enforcement sources.

Ferraro, who cited "delays" in the Justice Department probe when she announced last month that she would not run for the Senate from New York, has said she will not change that decision.

Department investigators, who interviewed Ferraro this month, plan to end the probe of her finances within weeks unless new information is found, the sources said. The case, opened in August 1984, remained at a preliminary stage and was never taken before a grand jury.

Stephen J. Pollak, Ferraro's attorney, said he had not been officially informed that the probe was near an end. But he said that would be "consistent with Ms. Ferraro's and our own expectations of what the outcome would be."

Pollak confirmed that the Justice Department had interviewed Ferraro Jan. 9 and her husband, businessman John A. Zaccaro, last November.

Ferraro was traveling yesterday and unavailable for comment, a spokesman said. She and her husband have denied wrongdoing.

The probe has focused on Ferraro's 1978 campaign finances in her first race for Congress and on her subsequent financial-disclosure reports as a House member representing Queens. Investigators have been examining whether she should have included her husband's finances in the statements and whether Zaccaro made illegal contributions to her 1978 campaign.

Ferraro had been widely expected to challenge Sen. Alfonse M. D'Amato (R-N.Y.), who has raised $6 million and holds a substantial lead in early polls. But Ferraro said last month that, while she had no doubt she would be vindicated, "if this investigation were still pending, the issue would be Geraldine Ferraro."

Ferraro offered herself this week as a replacement for Queens borough President Donald R. Manes, who took a leave of absence because of a federal investigation of his alleged role in a New York City corruption scandal. Queens officials chose Manes' deputy instead.

The Justice Department began investigating Ferraro after receiving complaints from the Washington Legal Foundation and a George Washington University professor. The complaints alleged that Ferraro falsely claimed on financial-disclosure forms that she was exempt from disclosing her husband's finances.

Records released by Ferraro in 1984 show that she was an officer in her husband's major business, P. Zaccaro Co., and that her husband's income was used to buy some joint assets, such as a vacation home.

The House ethics committee found several instances in which Ferraro did not disclose her husband's finances but said the violations appeared unintentional. It took no action against her.