Senate Majority Leader Robert C. Byrd (D-W. Va.) yesterday threw his weight behind proposals to "remove unreasonable restraints" on the CIA, and indicated that he expects congressional action on them this year.

Byrd, in his first weekly news conference since Congress reconvened, also predicted that "this will be a security-minded Congress" which will probably approve many of the president's requests for defense increases.

And he made clear that he expects a high level of political infighting as elections draw near. Taking a crack at the GOP, he indicated that he thinks Republicans will try to score political points through proposals for sweeping tax cuts and supermilitant action on the international front.

While Byrd didn't specifically endorse any one measure to set new ground rules for the CIA, which had its wings clipped in the mid-1970s after revelations of abuses, he made clear that he looks favorable on the concept of loosening some of the restraints, as favored by President Carter and Sen. Walter D. Huddleston (D-Ky.), who is working up legislation to do so.

Byrd said, "I anticipate legislation to remove unreasonable restraints."

For example, he said, he favors "reduction in the number of committees to which reports have to be made." At present, he said, the CIA must report on its activities to the intelligence committees and to the Armed Services and Foreign Relations committees. As far as he is concerned, he said, reports "should only go to the House and Senate Intelligence committees."

Moreover, he said, he agrees with the concept, on which Huddleston intends to propose formal legislation, of reducing the scope of CIA documents available to reporters and the public under the Freedom of Information Act.

And, Byrd added, "It ought to be a crime to reveal the names of CIA operatives when revealing those names may greatly jeopardize" not only their lives, but the success of major CIA operations.

The proposals to loosen the reins on the CIA, thought moribund some months ago, have gained considerable momentum as a result of the Iran crisis and the Soviet intervention in Afghanistan.

In another comment relating to Afghanistan, Byrd said he expects a resolution calling for removal of the Olympic Games from Moscow and U.S. nonparticipation if they are held in Moscow to pass the Senate this week "overwhelmingly."

Byrd also labeled as "a partisan position reflecting the attitude of the oil companies" a Republican proposal -- backed by 39 GOP senators -- to set a flat $227-billion now contemplated, but would prevent the figure from rising automatically if oil profits over the next decade are higher than now forecast.

Byrd also said he supports draft registration but that he hasn't any position on whether it should include women, though he said he wouldn't want to see them in combat.

Aside from appropriations and beefing up defense outlays, he said, he expects the Senate to concentrate on finishing all the major pending energy legislation, passing the president's youth employment bill, approving some form of legislation to improve Medicare benefits and guarantee all individuals protection against the costs of catastrophic illness, reducing regulatory restraints on small business.

And he said, "I don't think a tax cut should be ruled out at some point if conditions seem to indicate it," perhaps in a form of a "freeze" of the Social Security tax rate instead of letting it go up next Jan. 1, as scheduled in existing law.