A House Appropriations subcommittee agreed yesterday to freeze defense outlays this year, impose a moratorium on further testing of antisatellite weapons and reduce President Reagan's request for a "Star Wars" space defense system.

The actions were taken by the defense appropriations subcommittee as it completed action in closed session on the fiscal 1986 military spending bill.

The measure will go to the full Appropriations Committee for consideration sometime in the next few weeks. If approved by the House, it may lead to a clash with the Republican-led Senate, which is likely to approve outlays more in line with the president's requests.

In most instances the subcommittee actions mirrored votes taken by the Democratic-controlled House in June when it approved legislation authorizing fiscal 1986 defense programs.

As approved by the subcommittee, the appropriations bill would result in total defense spending this year of $292 billion, which freezes funding at the fiscal 1985 level.

In June the House approved a similar freeze when it adopted the defense authorization, but the Senate approved total spending that was $10 billion higher.

A House-Senate conference committee agreed to the higher number, provoking a storm of protest in House Democratic ranks that has held up final action on the conference agreement.

Democratic leaders have worked to defuse the hostilities through a deal that would make it difficult for the appropriations bill, and related defense spending legislation, to exceed the $292 billion freeze level. The subcommittee's action on antisatellite (ASAT) weapons similarly tracked what the House did on the authorization in June.

At that time the House voted to ban further tests of ASAT weapons as long as the Soviet Union continued a self-imposed moratorium on tests of its ASAT. The conference committee agreed to allow three tests regardless of the Soviet moratorium. The administration has already performed one.

Rep. Les AuCoin (D-Ore.) said yesterday the subcommittee agreed to a ban in part because of the recent test. "We hope if we curtail it now it will put the ball in the Soviet court and they won't resume their tests," AuCoin said.

On Star Wars, officially known as the Strategic Defense Initiative, Rep. Norman D. Dicks (D-Wash.) attempted to cut the administration request of $3.7 billion to $1.9 billion. But the subcommittee voted instead to provide $2.5 billion, an increase of more than $1 billion over fiscal 1985.

The House approved $2.5 billion for Star Wars in June but the conference committee agreed to $2.75 billion. On Wednesday, Defense Secretary Caspar W. Weinberger had breakfast with the subcommittee and told the lawmakers that $2.75 billion for Star Wars was needed to show strength to the Soviets before the Nov. 19-20 summit between President Reagan and Soviet leader Mikhail Gorbachev, subcommittee members said. The argument did not persuade many.

"My best value judgment was that even at that level [$2.5 billion] it's a healthy, strong program," said Rep. Joseph M. McDade (R-Pa.), the ranking Republican.

Dicks said he and others will try in the full committee, which is less conservative than the subcommittee, to cut funding for Star Wars even further, to between $1.9 billion and $2.1 billion.

In other actions, the subcommittee provided funds to resume production of nerve gas for the first time in 16 years but attached several conditions that had been dropped by the conference.