Freshman Sen. John W. Warner (R-Va.) told an Arlington audience yesterday that he and his senior Virginia colleague, Independent Sen. Harry F. Byrd Jr., are "lonely voices" fighting for reduced U.S. spending.

"We're trying the best we can to limit federal spending," Warner told a joint meeting of the Arlington Chamber of Commerce and the Greater Rosslyn Business and Professional Association. "You are getting your money's worth from these two senators."

Warner's praise of Byrd and of their similar voting records was the clearest indication yet that the new senator is anxious to be aligned with Byrd, the former Democrat whose influence in Virginia politics transcends party affiliation.

Warner pointed to a vote Tuesday night in which he and Byrd were among only 17 senators who voted against a $350 million addition to the proposed federal budget, an action the majority of the senators apparently felt was necessary to break an impasse with the House-passed version.

In the last two days Warner and Byrd have cast six identical votes in favor of budget cuts. Other issues on which their voting records have matched include support for voluntary school prayers, gas rationing, continued recognition of Taiwan, cutting CETA funds and against a new Department of Education.

An analysis of Warner's voting record shows that he has voted with Byrd 80 percent of the time, usually on the losing side.

Of 115 recorded votes in the Senate so far this year, the two Virginians have voted alike 92 times. Included among the 23 votes on which they differed were five straight party organizational matters in which Byrd voted with the Democrats.

The Virginia senators have differed mostly on spending issues. Warner has voted for and Byrd against: military aid to Turkey; funds to implement the Mideast peace treaty; increased Social Security benefits and meals on wheels for the elderly to keep up with inflation; funds for the Law Enforcement Assistance Administration, and to help stop the flow of narcotics from Columbia. In each instance, Warner voted with the majority.

Neither Warner nor Byrd has missed a recorded vote this year.

Warner told the luncheon audience at the Rosslyn Ramada Inn that he and Byrd are among 25 senators "working for a constitutional amendment that will require Uncle Sam to balance his books, either by spending no more than he takes in or by limiting spending to a percentage of the gross national product."

Warner's 30-minute appearance was interrupted twice by applause - when he said he opposed the SALT agreement unless it is amended, and when he promised he would take "no foreign trips" during his first year.

"I am staying home," he said. His predecessor, former Sen. William L. Scott, visited about 40 foreign countries during his single term in the Senate.

A spokesman for Byrd said that the two Virginia senators are "somewhat more cooperative" than were Scott and Byrd, especially in relations between their staffs.

The Byrd aide recalled that Warner was "one of, if not the first" senator to join in Byrd's resolution that would require Senate approval of the abrogation of defense treaties. Byrd's resolution, which did not succeed, was in reaction to President Carter's recognition of China.

"They are philosophically the same" on issues such as protecting Taiwan and cutting the budget, the Byrd aide said.

Four months ago, when Warner first went to Capitol Hill, he sought out liberal Rep. Herbert E. Harris II (D-Va.), saying he wanted to cooperate on issues of mutual concern.

That odd-couple alliance prompted some observers to believe Warner would be more moderate than most members of the largely conservative Virginia congressional delegation. Warner said at the time that his voting record would be moderate-to-convervative.

An aide to Harris yesterday said "It was always clear" that Warner and Harris would cooperate on specific issues of interest to their constituents, but "it was never a political alliance."

The two Northern Virginians continue to meet. Harris went to Warner's office as recently as last week to urge the senator to support a bill to expand the Manassas battlefield park.