Bonnie Nora Davenport, the formerly male police officer who underwent a sex change operation recently, has been certified fit to return to duty on the District of Columbia police force as a policewoman -- the city's first transsexual officer.

Davenport, 35, said yesterday she was overjoyed. She said she hopes to resume work next week.

Doctors at the D.C. Fire and Police Clinic issued Davenport's fitness certificate earlier this week, paving the way for what is expected to be routine approval and reinstatement of the eight-year veteran by police department personnel officials.

The doctors cautioned that Davenport should perform only light duty until she completely recovers from her sex change surgery two months ago. In addition, they said, she should continue precautionary psychiatric counseling for an indefinite period.

The bureaucratic chain of events leading toward her reinstatement started almost a year ago when Bonnie -- then Ormus W. Davenport III -- went on leave without pay from the police department in preparation for the sex change surgery. This involved hormone treatment, psychiatric therapy and living in a female work role.

The operation was performed in late November at a hospital in Trinidad, Colo., by Dr. Stanley Biber, a specialist in "gender conversion" surgery.

In early January, Davenport went before the fire and police clinic to seek reinstatement as a policewoman. After a series of physical and psychological tests -- the same tests given all officers returning from extended leave -- the clinic certified her fit for duty this week.

To hasten her reinstatement, Davenport hand-carried her clinic papers and court documents certifying her name change to police headquarters.

Routine approval by personnel officials and Police Chief Burtell Jefferson is expected, police officials familiar with personnel procedures said. They noted yesterday that an antidiscrimination executive order issued by former Mayor Walter E. Washington was extended in 1975 to cover employes who undergo sex changes. With Davenport's certificate of medical fitness, officials said, there is thus little standing in the way of approval. Jefferson declined to comment.

All that remains is for Davenport's personnel records to be amended to reflect her new gender and for her to be assigned to duty, possibly by Monday, officials said.

Because of her long absence from the force, Davenport will probably he assigned to undergo some retraining, including firearms qualification, the officials said, before she is put on regular street duty.

The D.C. Police Department has long been a pioneer in hiring females and minorities. There are now about 300 women on the 4,200-member force and almost 2,100 blacks -- both substantially higher percentages than in any other major city police department in the country.

In an interview yesterday, Davenport said she expects some initial adjustment problems and a "certain amount of peer pressure" from some fellow officers.

"But I also have a lot of friends at the police department," she said.

Davenport, as a male officer, was assigned to the 2nd and 4th police districts and worked as an undercover operative.

"So there's a certain amount of mutual respect for each other," she said yesterday. "I'm just going to roll with the punches, if there are any."

Davenport said she agreed with the fire and police clinic recommendation that she continue psychiatric counseling "to avoid serious problems later on in life... After all, I'm only two months old as a female."

Surgeon Biber said Davenoport had been a "good patient with excellent evaluations."

The operation involved removal of Davenport's male sexual organs and surgical construction of female organs. Biber said Davenport is normal except that she has no uterus and cannot bear children.

Formerly married and a widower Davenport has three children, two boys and a girl, 11, 12 and 13, now living with grandparents. As a male officer, Davenport had done undercover work in the 4th District, embracing the upper 16th Street-Georgia Avenue area of Northwest. She said yesterday she hopes to be reassigned to that district.

In her previous undercover work, she was assigned to the celebrated "Sting" phony police undercover fencing operation in 1976 and the subsequent "Gotcha Again" operation. Scores of burglary and fencing suspects were arrested in the joint FBI D.C. police operations.