The Senate voted 59 to 39 yesterday to join the House in releasing funds for the MX missile, but the five-day debate suggested that continued support for the controversial nuclear weapon depends on continued administration flexibility on arms control.

The Senate vote, which President Reagan hailed as "a decisive, historic contribution to our national security," allows the administration to spend $625 million this year for basing studies and test flights of the 10-warhead missiles that the Air Force plans to deploy in existing Minuteman silos in Nebraska and Wyoming.

The House agreed Tuesday to release the funds that Congress held up last winter. But Congress will have other chances to vote on the MX in coming months in the fiscal 1984 funding bills.

Members in both chambers are preparing amendments to those bills to continue influencing the administration's positions in the arms control talks with the Soviet Union in Geneva.

"I don't think there should be any popping of champagne bottles," said Sen. Dan Quayle (R-Ind.). "The MX alone would not get 35 votes in this chamber. But the reason it will pass is that we are voting for MX and for arms control."

Moderate Republicans seemed especially uneasy over supporting the MX. "My vote is a tentative vote," warned Sen. Arlen Specter (R-Pa.). "It is based on what the president does on arms reduction. The evidence of the value of the MX as a weapon is unconvincing."

"Since this is only a milepost on the road to MX deployment," said Sen. Charles McC. Mathias Jr. (R-Md.), "I am reluctantly willing to agree to this appropriation, but only on one condition . . . . The administration must produce some evidence that it is willing to adopt a new arms control strategy."

Maryland Democrat Paul S. Sarbanes voted against the funds, whereas Virginia Republicans John W. Warner and Paul S. Trible Jr. voted in favor of them.

Republicans supported the missile 47 to 6. Democrats opposed it 33 to 12.

Last December Congress blocked the MX funds out of dissatisfaction with the administration's plan to bunch 100 missiles in a "Dense Pack" on the theory that the first incoming Soviet missiles would blow up those following.

The Senate's vote at the time was 56 to 42 in favor of delay.

In an effort to salvage the MX, Reagan then appointed a bipartisan commission headed by Brent Scowcroft, former national security affairs adviser in the Nixon and Ford administrations. In April, the president endorsed the commission's recommendations to place 100 MXs in Minuteman silos for now, but look in the future to a smaller, mobile single-warhead missile that arms control advocates think would be less fearsome.

Reagan also pledged to develop a new arms control position that would seek to reduce the ratio of warheads to silos, and said he would explore the so-called build-down idea of scrapping old warheads when new ones are deployed.

Several senators voting for the missile, however, said they would support a resolution co-sponsored by Sens. Carl Levin (D-Mich.) and Sen. Nancy Landon Kassebaum (R-Kan.) to urge suspension of all flight tests on the MX if the Soviets also halt flight tests of land-based missiles.

The Levin-Kassebaum resolution was blocked on the floor by Majority Leader Howard H. Baker Jr. (R-Tenn.), who said it "is not appropriate to dilute the decision on the MX."

Levin plans to bring up the resolution after the Memorial Day recess. "This is going to be the new battleground on the MX," he said.

Noting the politically charged nature of the issue for Democrats, Levin said that if the MX is killed, "The Reagan administration would be tempted to load all the blame for arms control failure on the vote to kill the MX."

However, four Democratic senators who are vying for the 1984 presidential nomination weighed in against the missile.

"Anyone who believes that this administration--which has consistently demonstrated its lack of support for real arms control--will suddenly pursue arms control with vigor, is sorely mistaken," said Sen. Alan Cranston (D-Calif.).

"There is no logic, no justification in proceeding with a missile that will cost us more than $26 billion when it has no essential military role, no satisfactory basing mode and when it will be replaced in a mere five years."

Sen. John Glenn (D-Ohio) said "SALT II is dead if we pass the president's MX program."

That strategic arms limitation treaty, which was not ratified but which the United States and Soviet Union have pledged to honor, allows only one new missile to be tested on each side.

If the MX is tested, development of a second single-warhead missile would then be precluded, opponents argued.

Sens. Gary Hart (D-Colo.) and Ernest F. Hollings (D-S.C.) also spoke against the missile.

They too are presidential candidates.

However, Sen. Henry M. Jackson (D-Wash.) argued that the MX "is absolutely necessary as an incentive to Soviet leaders to persuade them that it is in their own national interest to seek strategic arms reductions. . . . Given our 10-year debate on the MX program, what credibility would the Soviets place in statements of our intent to deploy a small, single-warhead ICBM sometime in the 1990s?"