The Senate Armed Services Committee gave formal approval yesterday to a report on SALT II which concludes that approving SALT "is not in the national security interests of the United States."

After a bitter fight, and over the objections of its chairman, the committee adopted the report by a vote of 10 to 0. Seven senators who opposed issuing the report, voted "present," apparently to indicate their disdain for the procedure.

At a press conference given by eight of the 10 supporters of the report, Sen. Henry M. Jackson (D-Wash.), their spokesman, said SALT II was "a license for a massive buildup in strategic arms" that granted unilateral advantages to the Soviet Union.

Adoption of the report with 10 committee votes dramatized the Carter administration's failure to convince members of this most hawkish of Senate panels of the value of the strategic arms limitation treaty. When SALT hearings began last summer, administration lobbyists held out hope of building a 10 to 7 or 9 to 8 majority on the committee for SALT II.

But three senators who had to move toward the treaty to make those hopes come true joined the 10-vote majority that backed yesterday's anti-treaty report. They were Howard W. Cannon (D-Nev.), William S. Cohen (R-Maine) and John W. Warner (R-Va.). The seven others who voted for the report were all counted as SALT opponents months ago.

Sen. Gary Hart (D-Colo.), a SALT advocate, dismissed yesterday's result as "a plot" contrived by staff aides hostile to the treaty. He said it would have no significant impact in the final Senate vote on SALT II. Hart said that there were only about 15 members of the Senate who had declared their opposition to SALT II, and "nine of them are on the Armed Services Committee," so that this vote "in no way represents any shift of opinion in the Senate."

Jackson said SALT does not now have the 67 Senate votes it would need for approval. Asked if the treaty was dead, Jackson replied: "It's in a sort of state of repose."

The history of yesterday's report was unusual. It had been written by staff aides to anti-SALT senators, principally by Richard Perle of Jackson's staff, and circulated among likeminded senators before being considered at a committee meeting. Stories were leaked to the media that a majority of 10 or 11 members had approved the report before it was even seem by some members.

This left no real role for Sen. John C. STENNIS (D-Miss.), chairman of the Armed Services Committee, who opposed issuing any such document as inappropriate for the committee. But Stennis and the SALT supporters on the committee were outvoted. The committee never did consider all the specific points critical of SALT II contained in the report.

Members of the committee's majority defended their decision to issue a report recommending racical changes in or rejection of SALT II, while admitting that treaties actually fall within the jurisdiction of the Foreign Relations Committee. For example, Cannon said the Armed Services Committee simply was fulfilling its duty to report to the Senate on a matter releveant to national security.

Senators on the other side of the issue disgreed.

Carl LEVIN D-Mich.) said the committee had never before formally recommended against a treaty, and John C. Culver (D-Iowa) said he did not think committees should advise the Senate how to vote "on matters not within their legislative jurisdiction."

Report opens with a statement of concern that the Soviet Union has achieved the theoretical ability to wipe out America's land-based missile force with a sneak attack. The military balance is shifting against the United States, the report says, adding that even the administration's recently expanded defense-spending plans "are not adequate to close the gap . . ."

SALT II allows the Soviets to maintain a land-based missle force for superior to America's the report says. It criticizes numerical limits in the treaty that would force the United States to dismantle some of its best land-based or submarine-based missiles if this country wants to deploy large numbers of the new air-launched cruise missile.

The report says that the "new types" rule in the treaty, which limits each country to one entirely new type of missile and permits changes no greater than 5 percent in key characteristics of other missiles, will permit the Soviets to deploy an entire new generation of missiles designed to meet these criteria.

The senators voting for the report, in addition to Jackson, Cannon, Cohen and Warner, were Harry F. Byrd Jr. (Ind.-Va.), John G. Tower (R.-Tex.), Strom Thurmond (R-S.C.), Barry M. Goldwater (R-Ariz.), Roger Jepsen (R-Iowa) and Gordon J. Humphrey (r-N.Y.).

Those who voted "present," along with Stennis, Hart, Levin and Colver, were Sam Nunn (D-Ga.), Robert B. Morgan (D-N.C.) and J. James Exon (D-Neb.)