D. C. Police Chief Maurice J. Cullinane informed Mayor Walter E. Washington this week that he is taking steps to retire by Feb. 1, The Washington Post has learned.

Cullinane is scheduled to appear before the police retirement board next Thursday and, if the board grants his request for medical disability retirement, will officially retire Feb. 1, according to informed sources.

Approval of his disability retirement is likely, the sources said, making Cullinane, 45, eligible for tax-free retirement pay of more than $30,000 a year.Before Cullinane became chief in 1974, he suffered a serious knee injur during a 1969 antiwar demonstration.

In his meeting this week with the mayor, Cullinane submitted the names of three of his four assistant chiefs as candidates to succeed him, according to sources. Neither Cullinane nor the mayor has publicly indicated a front-runner for the politically and racially sensitive appointment.

But in police and city government circles, one of the assistant chiefs, Burtell M. Jefferson, the commander of the key field operations bureau who is known to be close to both Cullinane and the mayor, has long been considered the heir apparent.

If he is selected,Jefferson would become the first black chief of the 4,10*0-member city police force, which is currently about 40 per cent black. The population of Washington is about 73 per cent black.

A spokesman for mayor Washington yesterday would not confirm the recent Cullinane Washington meeting, but added, "I will not deny it." The spokesman also said Cullinane has not yet submitted retirement papers to the mayor.

It was learned, however, that Cullinane is seeking disability retirement and must therefore go before the five-member Police and Fire Retirement and Relief Board for approval. The board meets next Thursday, and sources said Cullinane will appear then.

A medical disability would entitle Cullinane to retire at about 70 per cent of his current $47,500 salary, tax free, which is substantially more than the pay for normal retirement.

In recent interviews, Cullinane had said he had no specific plans for retirement but did not intend to "set any longevity records."

He was appointed chief just three years ago, on Dec. 13, 1974, after a widely publicized search by a blue-ribbon committee headed by John T. Walker, then suffragan bishop of the Episcopal Archdiocese of Washington and now bishop.

A 19-year veteran of the police force at the time, Cullinane had been an assistant chief and a confidant of outgoing Chief Jerry V. Wilson.

In addition to Jefferson, the assistant chiefs now under consideration as Cullinane's successor are TilmonB. O'Bryant, head of administrative services, and Robert L. Rabe, in charge of inspectional services.

A fourth assistant chief, John Hughes, head of technical services, is nearing retirement and has indicated no interest in the top spot.

O'Bryant, who is black, and Jefferson and Cullinane were among five candidates recommended in 1974 by the Walker committee. O'Bryant reportedly had been a supporter ofClifford Alexander, an attorney and Secretary of the Army, who unsuccessfully challenged Walter Washington for the mayoral nomination in the 1974 Democratic primary, just prior to the search for a new chief to succeed Wilson.

Mayor Washington passed over O'Bryant, who was senior to both Cullinane and Jefferson in years of service, and chose Cullinane.

With Cullinane's appointment, Jefferson became assistant chief for field operations, a key position putting him in charge of the entire uniformed force.

Cullinane's appointment was interpreted by police veterans as a continuation of the progressive, community-minded image of his predecessor, Wilson. If Jefferson now succeeds Cullinane, insiders say this will be another extension of that image.

Assistant Chief Rabe is another possible contender for the chief's position. As former commander of the riot-trained special operations division, he gained a reputation as a skilled negotiator in various hostage and terrorist situations in recent years. Police department observers note however, that he has been an assistant chief for only a few months.

Rabe is white and, even though the mayor says color is not a consideration in selecting a police chief, the mayor is certain to come under pressure to appoint a black.

In addition to Cullinane's impending departure, D.C. Fire Chief Burton Johnson is expected to retire soon, compounding problems for MayorWashington who is considering running next year for re-election.

Johnson is black, but there are few other blacksin the fire department hierarchy from whom to select a successor. The 1,450-man fire department is about 30 per cent black.

In the competition for police chief, the deputy chiefs, who rank immediately below the four assistant chiefs, also may be considered by the mayor, but elevation of a deputy chief to the top post would be unusual.

The mayor also may consider applicants from outside the city as he did in 1974 when the other two of five candidates recommended by the Walker committee were police officials from other cities. Again, such an appointment now is not likely.

Cullinane, a Washington native who now lives in the Norbeck section of Montgomery County, is a quiet, undramatic man with a reputation for administrative efficiency.

During his three-year tenure, the incidence of reported crime generally has continued to decline, although not as steeply as under his predecessor.

Cullinane also has presided over several departmental innovations. He helped create a joint police-U.S. attorney's office "career criminal unit" to weed out recidivists and put them behind bars while awaiting trial.

Cullinane raised the rank of the department's seven district commanders from inspector to deputy chief, giving them more clout and deleting some bureaucratic layers between the districts and downtown headquarters.

Cullinane also was intimately involved in the joint police-FBI "Sting" operation and its successor under-cover fencing operations, which netted scores of arrests and convictions.

Cullinane joined the police force in 1955 and rose to assistant chief in 18 years. He served in a variety of street andoffice assignments, and at one time commandedthe uniform patrol division.

He and his wife, Carole,e have three children, Marie, 20, Jeanne, 18, and Joanne, 14.

Assistant Chief Jefferson, 52, like Cullinane, was born in Washington. He joined the police department in 1948 after completing one year of college at Howard University. He commanded the robbery squad in the early 1970s, and later was put in charge of the inner-city third district. He was promoted to assistant chief in late 1974.

Jefferson is divorced and lives in northeast Washington.