Mayor Walter E. Washington, formally announcing the appointment of Albert P. Russo as director of the Department of Human Resources, said yesterday that Russo should not be held accountable for the problems that have plagued the agency in the past.

Russo will succeed Joseph P. Yeldell, who was removed from the DHR directorship in April following a stormy five-year stint as head of the city's largest agency. For the past two years, Russo has been Yeldell's deputy and a top aide in DHR since 1972.

In response to a reporter's question yesterday as to whether Russo could be viewed as "part and parcel" of the administrative problems at the troubled agency, the mayor said, "He could."

The mayor added later, "I don't believe that Mr. Russo was the director or (that) he was a part of it. He has direct knowledge of it." The mayor went on to emphasize that Russo enjoyed his full confidence.

The mayor's announcement came at an afternoon press conference and reiterated intentions he voiced at a Capitol Hill "town hall" meeting Tuesday night that was sponsored by a citizens group that includes many of the mayor's strongest political supporters.

The announcement of Russo's accession removed a cloud of uncertainty about the leadership of DHR that has lingered for more than six months.

Russo said Tuesday night that the mayor's announcement surprised him. That surprise seemed to have been in timing only, since Russo had made it clear that he wanted to be appointed permanently to the post. Yeldell now is a general assistant to the mayor.

The mayor said his was a "non-racial decision based on qualifications of a man I believe could run the department." Russo is white. Some citizens have expressed concern about the appointment of a nonblack to head the largest agency in an overwhelmingly black city with a predominantly black elected government.

The mayor said no other candidates were seriously considered for the job, though he had informally talked to a number of people about the post.

"If you're asking me if I intended to do a nationwide search and take all the time that is involved in that, I didn't," the mayor said.

The mayor's urgency in filling the position stemmed from concerns by some that the department's operations could be hindered for as long as the directorship remained open.

The choice of Russo fit a pattern established by the mayor during his near-decade of service as the city's chief executive, in both appointed and elected positions.

Seldom in the selection of the more than two-dozen top administrators who head major city departments has Washington gone outside a close circle of past aides and associates, or previous department deputies.

Even in cases where nationwide searches have been held - such as in the selection of the police and fire chiefs, the city housing director and corrections director - deputies generally have been picked for those posts.

Corrections director Delbert L. Jackson, environmental service director Herbert L. Tucker, personnel director George R. Harrod and recreation director William H. Rumsey all were deputies who were elevated to the top by Washington when their bosses left.

Three other top aides to the mayor followed virtually the same path into top level posts in Washington's cabinet. City administrator Julian R. Dugas, housing director Lorenzo W. Jacobs and economic development director James W. Hill all were at various times director or associate director of Neighborhood Legal Services and later held top posts in the Economic Development Department. Hill is still there: Dugas and Jacobs have moved on.

James W. Baldwin, director of the D.C. Office of Human Rights, formerly was director of a community information service at the United Planning Organization, of which Neighborhood Legal Services is a part.

Yeldell, before being named DHR director, was a close political ally of the mayor's on the then appointed City Council. Corporation Counsel John R. Risher Jr. was the lawyer for the mayor's 1974 campaign organization.

The mayor's reliance on close associates for top departmental jobs has spawned some accusations of cronyism in his own administration and sparked some rows with the City Council, which has no confirmation power over the selection of department heads.