If his actions during the Democratic Midterm Conference held here over the weekend, were any indication, Mayor-elect Marion Barry intends to have a much higher national political profile than Mayor Walter E. Washington, the man Barry replaces Jan. 2.

When the talk turns to big city black mayors these days, the names usually dropped are those of Coleman Young of Detroit, Richard Hatcher of Gary, Tom Bradley of Los Angeles, Kenneth Gibson of Newark, Maynard Jackson of Atlanta and, more recently, Ernest Morial of New Orleans.

Washington of Washington might just as well be the name of a fashion designer, for it is seldom heard in such discussions. That seems somewhat remarkable, because the District's outgoing mayor has been in office longer than any other sitting cheif executive of a major city in the nation, and only Detroit and Los Angeles, among cities with black mayors, have larger populations than Washington, D.C.

Two days after winning the Nov. 7 general election, Barry said he intended to be "very active" in such nationwide municipal organizations as the National League of Cities, the U.S. Conference of Mayors and the National Conference of Black Mayors, even though, he said, "my priority will be the District government."

At the meeting here, there were strong indications that the mayor-elect was trying not only to get maximum political mileage from his southern outing, but also laying the groundwork for some future forays into the national arena.

He was co-leader of the city delegation to the conference, actively lobbied on behalf of a resolution urging ratification of a constitutional amendment granting the city full-voting representation in Congress and offered a one minute speech to the conference on the necessity of passing the resolution.

Barry was chairman of the conference workshop on education. Even though he arrived about 40 minutes late for the session, during much of the time he was there, he shared the center of the table-and the focus of the national news media cameras-with a not so obscure visiting panelist, Vice President Walter Mondale.

At the workshop on the nation's cities, Bary was one of the first to raise questions from the floor, placing a pointed query to panelist Jack Watson, who is President Carter's chief liaison with local and state governments. Barry's enthusiastically delivered question on possible cutbacks in spending for social services-including the Comprehensive Employment Training Act jobs programs-in the fiscal 1980 budget was well received by the audience, which included many municipal officials from throughout the country.

Afterwards, Barry was one of four persons elected by those attending the workshop to serve on a committee that will advise the Democratic National Committee on urban policy for the 1980 party platform. That position could give Barry the opportunity to make some-though clearly limited-imput into the platform. More importantly, it gives him an entree to a few people influential in the DNC.

All of this was not coincidental, said Florence Tate, Barry's press secretary. Barry is "experienced in philosophy and an activist in whatever position he is occupying," she said. "Marion Barry will be actively involved in the urban politics of his party and the country."

That was the indication Barry, who grew up in Memphis, gave to many of his old friends, former professors and others during the considerable time he spent away from the conference.

He spoke forcefully of the plight of blacks, at times dazzling his audiences with statistics about gaps in black and white earnings. As he had done at the conference, Barry tried to present an image of a young, black, new political face on the horizon. He appeared to be packaging himself as a politician knowledgeable about the complexities of the urban predicament, in tune with key Democratic constituencies (such as women's rights advocates), yet well-rooted in the black community.

"I'm not anti-integration. I'm not anti-white people. I'm just pro-black people first, and that's the attitude we've got to have. Isn't that right?" Barry told students during a session at his alma mater, tiny LeMoyne-Owen College.

The next night, speaking to more than 400 persons who had gathered at a "Homecoming Tribute" for him, the soon-to-be mayor told his home-town folk that they, too, would benefit from his election as mayor of the nation's capital. "I'm in a position to represent all black America," Barry said.

Barry was not afraid to make at least one campaign-like promise that he said he could fulfill in his new role. When the United Negro College Fund, which raises funds for 22 schools (including LeMoyne-Owen), holds a fundraiser in the district next week, Barry said, he will go into action.

"What I'm gonna do as mayor of the District of Columbia," he said, "I'm gonna make, urge, cojole and push that community-particularly the white business community-into supporting the United Negro College Fund."

Barry also plans to play a high-profile role in the push for nationwide ratification by state legislatures of the full-voting rights amendment, although, he has said, he will campaign for it primarily from his office in city hall.

"I'm not interested in travelling," he said. "I've traveled enough in my life. I want to stay right here and work for the citizens of the District of Columbia."

Barry did travel some after he won the election, but at the time refused to say publicly where he was going. Now the word is plainly out. Jamaica was his port of call. The mayor-elect, carrying his brief case and a couple of tennis rackets, was met upon arrival at the Donald Sangster Airport in Montego Bay by U.S. Consul Robert Garth and Eastern Airlines Manager Barry Foster.

Marion Barry was not the only member of the D.C. delegation elected as a member of a platform advisory committee at the Democratic Midterm Conference. D.C. school board member John Warren was chosen for the education advisory committee. Ruth Jordan, a member of the board of the Coalition of Labor Union Women, was chosen for the advisory committee on the economy and inflation.

J.C. Turner, general president of the International Union of Operating Engineers, attended the conference as a labor delegate. Turner was elected to the advisory committee concerned with the economy and jobs.