Republican Party leaders today rejected as "gimmickry" the call for a constitutional amendment to require a balanced federal budget and, instead, said the GOP would campaign in 1980 for lower taxes and tougher spending limits.

The issue sharply split members of Congress and state officials at a party conference here and left the losers complaining that their party may see another popular issue preempted by what one of them called "born-again Democratic fiscal conservatives."

After two hours of sometimes emotional debate, they found agreement on a bare-bones resolution blaming the Democrats for "mounting deficits" and calling on Congress to balance the budget in fiscal year 1981 and to consider immediately a constitutional amendment to "limit federal spending."

But Sen. Bob Dole of Kansas, one of the 1980 presidential hopefuls at the session, complained that the resolution "ducked the tough one" on the balanced-budget amendment, and Rep. E. G. (Bud) Shuster of Pennsylvania said it showed "we're nothing but pusillanimous pussycats."

Dole and his allies said the GOP should take the lead in pushing the balanced-budget amendment when hearings begin in House and Senate Judiciary subcommittees.

Twenty-five states have approved some form of petition calling on Congress to pass a balanced-budget amendment or call a constitutional convention for that purpose. With 34 states, there would be a mandate for Congress to take one of those alternatives.

California Gov. Edmund G. (Jerry) Brown Jr., a prospective Democratic challenger to President Carter's renomination, has endorsed the balanced-budget amendment, as have several GOP presidential hopefuls.

But Republican National Chairman Bill Brock, House Minority Leader John J. Rhodes (Ariz.) and Rep. Barber B. Conable Jr. (N.Y.), ranking minority member of the Ways and Means Committee, led a concerted attack on the amendment idea that succeeded in blocking it.

Accusing Brown of "demagoguery," Brock said it is a "very, very hazardous exercise" to write such a requirement into the Constitution.

"I just don't like gimmickry," Rhodes said. "I think the Republican Party should tell the American people there's nothing easy about this... and if they want a balanced budget, they should elect a Republican Congress."

Warning against "constitutional Russian roulette," Conable said, "We Republicans understand the frustration of the people, but we believe in caution.... The Constitution should not be the repository of all kinds of nitpicking amendments."

But the conference resolution approving a constitutional limit of undefined strictness on federal spending was termed "only half a loaf" by Rep. Robert McClory (Ill.), ranking Republican on the House Judiciary Committee.

"Unless we want another popular issue, a Republican issue, to escape from us, we have to speak to the balanced budget issue," he said.

Dole, who has introduced an amendment requiring that taxes and spending be cut to 18 percent of the gross national product within three years, echoed the warning that the amendment "is a Republican issue and we're about to lose it."

But, in the end, constitutional caution prevailed over the desire for proprietorship of the fast-moving cause. By a two-vote margin, 34 to 32, the conferees declined to open the draft resolution to change. That result was later reversed by a 41 to 27 vote, but only to add some rhetoric accusing the Democratic majority in Congress of failing to "discipline itself to bring spending within reasonable limits."

The issue cut across normal ideological lines, with such staunch conversatives as Rep. Jack Kemp (N.Y.) and Sen. James A. McClure (Idaho)taking the cautionary stand, while Dole and McClory went the other way.

The debate closed the second Tidewater Conference, an annual gathering of elected GOP officials chaired by Sen. Bob Packwood (Ore.). Earlier, the conference approved a resolution calling for "substantial phased reductions in federal income tax rates" and indexing of the tax system to offset inflation.

Brock told reporters he was "not at all fearful" of the political effects of shunning the balanced-budget amendment. "We're talking too much about the budget, as if it was a panacea," he said. "Inflation isn't caused just by deficits."