President Reagan yesterday did some last-minute lobbying against the nuclear freeze resolution, which is scheduled for a vote in the House today. He met with 25 House members of both parties but, despite his efforts, Speaker Thomas P. (Tip) O'Neill Jr. (D-Mass.) predicted that the resolution will pass by 40 to 50 votes anyway.

"It's an easy vote," O'Neill said. "There's a frightened attitude of the people whenver they think of nuclear war . They would like America to get to the peace table on this issue."

But the White House continued to fight the freeze. At a Senate Armed Services subcommittee hearing, Richard Perle, assistant defense secretary for international security policy, said the freeze would serve only to "undermine the president's ability to negotiate."

The White House also announced that it supports an amendment to the resolution proposed by Rep. William Broomfield (R-Mich.) stating that the resolution is not intended to stop the modernization of American weapons systems.

White House spokesman Larry Speakes acknowledged that the White House outlook on the the vote is "not promising. It will be an uphill battle for us."

On Capitol Hill, O'Neill was confident that the resolution, without any amendment, would win easily "because it only expresses the will of Congress and does not bind the president." He predicted that the vote would not carry over into increased opposition to defense spending.

The resolution expresses, he said, "the will of the American people that they want to get to the peace table. There's a frightened attitude of people whenever they think of nuclear war."

Although Secretary of State George P. Shultz was expected to speak against the freeze to a closed Republican caucus this morning, it did not appear that the administration was preparing to mount the kind of lobbying campaign against it that they did last year when Reagan called wavering House members to change votes at the last minute.

"He doesn't have any time to mount a big campaign," O'Neill said.

Rep. Jim Leach (R-Iowa), a principal sponsor of the freeze resolution, said, "I don't see a full-court press. The administration is recognizing defeat on the House floor and its main intent is to discredit the freeze advocates."

In a breakfast meeting with reporters, Senate Foreign Relations Committee Chairman Charles H. Percy (R.-Ill.) said that freezing nuclear weapons at current levels when the Soviets have far more missiles deployed in Europe would be a "disaster," but he added that the resolution before Congress had been "vastly improved since it does call for deep reductions."

He said freeze advocates were "absolutely not" motivated by the Soviets and that, in the delegation of 500 who recently met with him, "I knew half the people. They are concerned, decent, highly motivted people. They are ministers, labor leaders, doctors. They have a deep desire to end the arms race."

Percy called for "a new face, a fresh approach" in the negotiations with the Soviet Union over intermediate-range missiles in Europe, and suggested that either Shultz or Deputy Secretary of State Kenneth W. Dam negotiate with the Soviets in Geneva.