President Reagan wants Commerce Secretary Malcolm Baldrige to become another Cabinet voice in nuclear weapons policy-making in addition to Defense Secretary Caspar W. Weinberger, according to administration sources.

The idea is reflected in Reagan's proposal to transfer the nation's $6 billion nuclear weapons building program from the Department of Energy, when and if it is dismantled, to Commerce. Weinberger opposed that proposal, saying the weapons program would have to compete with the department's civilian programs for funding.

Reagan's decision irritates not only Pentagon officials and Capitol Hill military experts but also scientists and officials throughout the nuclear weapons community who believe the transfer of the nuclear weapons building program was urged by Energy Secretary James B. Edwards and Office of Management and Budget officials who were ignorant of the program's size and varied activities.

The White House has formed a new task force that includes Baldrige, Edwards, and presidential counselor Edwin Meese III to take another look at the nuclear weapons program and organize the transfer program, according to a Reagan aide. The White House is aware, this aide said last week, that it faces an uphill battle to get congressional approval of a plan to implement the president's decision.

In size alone, Baldrige's $2 billion department would experience a major change if Congress approves the president's proposal. The nuclear weapons building program would make up almost 75 percent of Commerce's fiscal 1983 budget, which the Office of Management and Budget is now drawing up as if the change had taken place.

According to White House sources, Baldrige did not seek the program, which is run by the Energy Department. It was handed to him after a Cabinet council study chaired by Edwards recommended it be placed in either the Interior or Commerce departments. Weinberger, according to White House sources, was not included in the study and got into the picture only on his own initiative, late in the process. He and his deputy, Frank Carlucci, opposed the notion of putting the program in Commerce or any other civilian department.

In the final Cabinet committee session, with the president listening, the defense secretary instead strongly advocated making the nuclear weapons complex either independent or part of the Defense Department.

The nuclear weapons decision has been one of the few controversial, bureaucratic battles requiring a Reagan decision that Weinberger has lost.

Capitol Hill critics say the decision was tilted toward Baldrige, "a rising star in the administration," according to one source, because the commerce secretary's frequent horseback riding trips with the president have made him a Reagan favorite.

In addition, they say, Baldrige is looking for things to do since budgetary cutbacks have eliminated some of his grant programs and reorganization separated some others. Baldrige also came to Washington hoping to play a role in the administration's financial policy making, but like many commerce secretaries before him, was quickly shut out from a major role in it.

A top-ranking government scientist said recently that Commerce "is not a viable place" for the nation's $6 billion nuclear weapons building program "if the president is serious about it."

His statement was primarily a response to Edwards' reasoning that Commerce was chosen because of its experience in handling scientific programs such as the National Bureau of Standards.

Most critics are concerned with the weapons building program's ability to compete with civilian programs for funds in a civilian agency. Critics have complained that since the Atomic Energy Commission folded six years ago the weapons complex has not been able to get enough funds to keep its World War II facilities modernized or even safe.

They also worry that future commerce secretaries, and their choices to run the program, will be appointed because of qualifications other than expertise in nuclear weaponry.

The nuclear weapons complex includes the two laboratories at Los Alamos, N.M., and Livermore, Calif., and the associated Sandia laboratories.

It also consists of five manufacturing and assembly plants spread across the country that produce the parts for all the nation's nuclear warheads. It also runs the Nevada nuclear testing site, which also is a research facility on permanent means of storing the enormous amount of high level nuclear waste created by the 35-year-old nuclear weapons program.

The nation's four giant production reactors in Richland, Wash., and Savannah River, S.C., are part of the complex as are non-weapons testing laboratories in Idaho and Chicago.

The complex also plays a major role in arms control policy, developing the equipment to verify test bans through on-site and satellite techniques.

One critic cited Edwards as an example of how little knowledge of the complex went into the dismantling decision. Edwards continually referred to his cutting the number of DOE employes from 19,000 to 11,000, this source said. "What he didn't point out was that there are about 30,000 employes in the nuclear weapons complex and the size is growing under the Reagan budget."

Edwards, he said, did not visit the Los Alamos laboratory until Dec. 4, by which time he had already done his study and made his recommendations. "He learned a lot then for the first time about what the nuclear weapons program was about," this source said.