The University of Maryland is preparing for unprecedented layoffs in its central office today as the result of a decision by the Board of Regents to abolish nearly 100 of 230 positions.

The layoffs, approved at a closed meeting of the regents last night, follow the advice of a management consultant hired last winter to recommend ways to streamline the university's central administration.

Sources said last night that officials intend to notify the affected employees today. They said they were uncertain how many people would lose jobs, because about 30 of the office's 230 positions are vacant.

The regents had been scheduled to make the decision next week, but a university spokeswoman said last night that their decision was accelerated "out of consideration for the employees involved."

Last week, two of the university's five vice chancellors were told their jobs were recommended for elimination, creating a wave of anxiety throughout the central office, which is near the College Park campus, about further layoffs that were pending. "It is so upsetting," said one secretary, an employee of two decades who asked not to be identified but said she believed she would lose her job. "People have lost sleep. People have lost weight."

Interim Chancellor James A. Norton said he was not certain which positions the regents decided to abolish at their closed meeting. Norton is scheduled to leave the university tomorrow to make way for incoming Chancellor Donald L. Langenberg.

Another administration source said the university intended to announce the cuts publicly tomorrow, after the affected employees were notified.

The reduction is in response to a directive of the Maryland General Assembly, which requested cuts in the administration as part of a 1988 university system reorganization.

Last winter, legislators complained that the cuts had not yet taken place, prompting the regents to hire the management consultant to study what duties and positions in the central office should be eliminated.