The Reagan administration, reversing more than a decade of federal policy, plans to argue before the Supreme Court that an educational institution may continue to receive federal funds for some purposes even if some of its other programs discriminate against women.

In a court brief, obtained by The Washington Post and scheduled to be submitted Monday to the court, the Justice Department argues that a law forbidding discrimination against women does not apply to the entire institution receiving federal funds, only the specific program being funded.

The Justice Department has argued in the past that under the law (known as Title IX), in effect since 1972, institutions receiving any federal aid are barred from discriminating in any program.

Spokesmen for the Justice Department said last night there would be no comment on the brief.

The case involves Grove City College in Pennsylvania. It arose in 1978 when the Department of Health, Education and Welfare asked federal grantees to sign assurances that they would comply with Title IX. Grove City College refused on the basis that although its students received federal grants and loans, the college itself received no federal money.

HEW warned the school that it would cut off federal aid to Grove City's students, and the college went to court. The college has lost at the district and federal court levels, but other federal court rulings have been inconsistent.

The Justice Department brief says that Grove City should be asked to certify non-discrimination only in the awarding of federal financial aid. But the government will not ask for a certification of non-discrimination in other programs, including athletics, housing and access to special courses.

Representatives of civil rights groups complained bitterly yesterday that President Reagan was backtracking on women's rights the day after he made a speech to the American Bar Association pledging to "assure that every woman has an equal opportunity to achieve the American dream."

Margaret Kohn, a lawyer at National Women's Law Center, warned that such a change could also affect enforcement of laws prohibiting discrimination based on race, national origin or handicaps because those statutes have been drawn along parallel lines.

"Women's and civil rights groups are very distressed about the government taking this position. For the president to say on one hand that he supports the rights of women and then to take this position is inconsistent. The two positions are diametrically opposed."

Kohn has filed a motion in the Supreme Court asking to be allowed to present arguments in the case.

Ralph Neas of the Leadership Conference on Civil Rights, an umbrella organization of 165 civil rights groups, said, "Such a regressive action would demonstrate once again that the Reagan administration's record on civil rights is a marked contrast to the administration rhetoric of the past few weeks."

Meanwhile, Rep. Claudine Schneider (R-R.I.) has introduced a resolution to clarify that the law should be applied broadly to any institution receiving any federal assistance. The resolution already has 220 co-sponsors, including House Minority Leader Robert H. Michel (R-Ill.) and Rep. Jack Kemp (R-N.Y.). She plans to meet with White House officials Wednesday to try to persuade the administration to change its position.

"The legislative history has been clear," said Schneider, "The Justice Department should certainly determine that all sexual discrimination in federally supported educational institutions should be prohibited, not just in special programs but in the institutions as a whole."