Defense Secretary Harold Brown appealed to the AFL-CIO leadership here today to support President Carter's proposed reinstatement of mandatory registration for a military draft.

None of the federation's executive council members who met privately with Brown for about an hour today would react publicly to what one called the secretary's "low-keyed request."

But several AFL-CIO leaders said on background that they expect the 35-member council to back the president's registration proposal at the close here of the federation's 24th annual midwinter meeting early next week.

"I'm certain we'll support the call for registration," said one council member. He said the council's resolution committee on military registration probably will announce its support Friday and then put the question before the full council.

"Certain issues, such as the question of women in combat, remain unresolved," the council member said.

Brown told reporters after his meeting that he opposes putting women in combat because Pentagon and other studies have shown that such placements would have "a rather bad effect on the morale and effectiveness" of male combat troops.

"I believe that the situation that now exits in the Army where women are allowed to serve in 95 percent of the positions [exclusive of combat] is the correct one," Brown said.

He said his appearance before the AFL-CIO executive council, his first formal meeting with the leaders of the nation's top labor federation, came about because of an invitation from AFL-CIO President Lane Kirkland.

"I was particularly pleased to be able to address the AFL-CIO leadership because, as I told them, the country owes the AFL-CIO a great deal of thanks for its support of the nation's defense program," Brown said.

He said none of the council members questioned the administration's handling of defense matters Major questions from the federation's leadership concern the equity of past U.S. draft and the quality of crisis support from America's allies, Brown said.

On the draft question, the secretary said: "I said to them that, in my judgement, past drafts have been inequitable and that in the future, (draft) exemptions should be virtually nonexistent."

Brown said the labor leaders insisted that in times of international crisis that "sacrifices on the part of allies be equal." t

Kirkland skillfully evaded any substantive comment on the Brown meeting.

"We had a free-wheeling discussion with a number of intelligent and pentrating questions," he said.

Asked if he personally supports Carter's call for reinstating military registration, Kirkland said: "My personal feelings are that I will support whatever action the executive council takes."

Besides the registration question, the council will also consider possible federation action s on matters affecting the nation's imagery, foreign production, health care, unemployment, and general economic policies. Though the AFL-CIO will not endorse any presidential candidate until after party nominating conventions next summer, the council members are also heavily involved in meetings with the campaign officials representing all of the major Democratic candidates.