The reaction yesterday to President Reagan's first nomination to the Supreme Court was an ironic one: he was condemned by conservatives who supported him all the way to the Oval Office, but praised by liberals and feminists who have found so little to like about him there.

The Rev. Jerry Falwell, head of Moral Majority, declared that the nomination of Sandra D. O'Connor to the high court was a "disaster." The National Right to Life Committee, a major anti-abortion group, pledged an all-out fight against her confirmation because of "her consistent support for legal abortion."

But Eleanor Smeal, president of the National Organization for Women, called the nomination "a major victory for women's rights." And prospects for a quick and relatively painless confirmation appeared good.

Among the first to jump aboard O'Connor's bandwagon were Sen. Edward M. Kennedy (D-Mass.) and Rep. Morris K. Udall (D-Ariz.), two of the most outspoken liberals in Congress.

"I'm really quite pleased," said Udall, who has known O'Connor as a lawyer, state senator and judge. "She's about as moderate a Republican you'll ever find being appointed by Reagan. If we're going to have to have Reagan appointees to the court, you couldn't do much better."

"President Reagan should be commended for naming a woman to the Supreme Court -- the first such nominee in our nation's history and one that is very long overdue," said Kennedy.

His words were echoed by feminist leaders. "Justice O'Connor's nomination will be a major step in moving toward equal justice in every court in our land," said Iris Mitgang, chairman of the bipartisan National Women's Political Caucus.

Senate GOP leaders pledged to work for a swift confirmation. Majority Leader Howard H. Baker Jr. (Tenn.) said he was "delighted." Judiciary Committee Chairman Strom Thurmond (S.C.) said, "I will do everything I can to help the president."

The Reaction from the New Right could hardly have been more different. Richard Viguerie, the conservative direct-mail expert, accused Reagan of rushing O'Connor's nomination because of growing opposition on the right to reports of her selection.

Others accused Reagan of betraying the Republican platform. In one of its most controversial planks, the GOP platform pledged: "We support the appointment of judges to all levels of the judiciary who respect traditional family values and the sanctity of innocent human life."

"O'Connor's appointment represents a repudiation of the Republican platform pledge. . . . This appointment is a grave disappointment to the pro-life public nationwide," said Dr. J. C. Willke, president of the National Right to Life Committee, which supported Reagan in the 1980 campaign.

The words from Falwell's Moral Majority were even harsher: "Either the president did not have sufficient information about Judge O'Connor's background in social issues or he chose to ignore that information. . . . Judge O'Connor also has been active in feminist causes and is a supporter of the Equal Rights Amendment, which Moral Majority believes would be a disaster for men and women and would further undermine the traditional family." d

Anti-abortion groups focused their opposition to O'Connor on votes she cast while a state senator and on the fact that she once spoke, as a judge, before an International Women's Year meeting.

In 1974, she voted against a rider to a football stadium bond issue that would have barred abortions at the University of Arizona hospital, according to NRLC.That same year she reportedly voted against a resolution calling on Congress to pass a Human Life Amendment in the state Senate Judiciary Committee and in the Senate Republican caucas.

In a 1970 party caucas, she also voted in favor of a bill to legalize abortion, and in 1973 was a prime sponsor of a family planning bill that would have made birth control information available to minors without the knowledge of their parents. That same year she voted for a bill giving doctors and nurses the right to refuse to participate in abortion operations.

Dr. Carolyn Gerster, former president of the NRLC, said she notified the White House Monday about the alleged pro-abortion votes, and mailed a package documenting her charges. Gerster, a Scottsdale, Ariz., physician, said, "It was common knowledge she was philosophically against us in the legislature. It is unforgiveable that the White House could ignore this."

But O'Connor also has powerful Republican friends in her home state. The most important among them is Sen. Barry Goldwater, who called her nomination "a great step." After being notified of the nomination by Reagan, Goldwater said he doubted if the president "could ever find anyone more qualified to occupy a Supreme Court seat than Sandra O'Connor, whom I have known for years and greatly respect and admire."

Such words will weigh heavily even among hard-core Senate conservatives. "I assume that if she meets the satisfaction of the president of the United States and Barry Goldwater, she must have some basic philosophy I agree with," said Sen. Charles E. Grassley (R-Iowa).