The Reagan administration's proposed budget cuts will do "irreversible damage" to the conduct of scientific research in this country, a prominent group of scientific leaders warned yesterday.

"The expressed goals of this administration for a strong economy and improved national security demand more, rather than less, investment in basic research," the group concluded after a two-day meeting at the National Academy of Sciences here.

Strong support for basic research is necessary, they said, to guard against "critical" shortages in the number of scientists and engineers. One researcher predicted a return to the "pre-Sputnik" era, for example, in the nation's supply of physical scientists, given the projected cutbacks.

If additional research and development funds are not forthcoming, however, the academy president, Dr. Frank Press, said the nearly 100 participants from academia, industry and national laboratories had agreed that the following steps could help "minimize the damage":

* Funds should be reallocated between federal research and development programs to provide "greater protection" for the research side. The group also favored devoting a "larger part" of the defense R&D funds to "basic research."

* A review of the "entire science and technology enterprise," and the manner of funding, should be undertaken by the government, perhaps in the office of the president's science adviser.

* A "much strengthened mechanism" is needed for the scientific and engineering communities to advise the government on resource allocations and the impacts of various budget strategies.

The proposed overall federal budget for research and development in fiscal 1982 would be about $40 billion, according to the latest administration numbers, with roughly half of that defense-related.

An analysis of those numbers by Willis Shapley, a consultant to the American Association for the Advancement of Science, notes that if inflation were taken into account, this would mean a 26 percent increase for defense over fiscal 1980. Overall basic research, however, which is only about one-eighth of the total, would drop by 11 percent.

The gathering of scientists in Washington attracted an array of administration officials, including President Reagan's science adviser, Dr. George Keyworth, who advised them to be "realistic" and not paint the "worst scenario" as to the impact of the cuts.

Academy President Press, science adviser to then-President Jimmy Carter, emphasized at a news conference that the session, which he characterized as "unprecedented," was not intended as a "lobbying effort."

It was evident, however, that he and the other participants hoped that their message would be received not only by the administration but also by Capitol Hill. "We expect Congress will not be as severe," said Press.

He noted that scientific research is particularly vulnerable to unexpected budget changes, which can mean the disruption of entire research teams because "the cycle" for "building" and "rebuilding" science is on the order of "five to 10 years."