A Fairfax County juvenile and domestic relations court judge, whose husband was a campaign aide to Virginia Gov.-elect Charles S. Robb, is likely to become the first woman to be elected to a circuit court judgeship in Virginia, court and political officials predict.

Johanna L. Fitzpatrick, 35, generally is acknowledged to be leading a field of more than a dozen candidates who met Friday's filing deadline for nominations to fill what could be three vacancies on the Fairfax County Circuit Court, according to officials at the court and the Fairfax Bar Association. She is the first woman ever named to a judgeship in the county.

Fitzpatrick, whose husband worked as a press spokesman for Robb in his recent campaign, is reported to be the choice of Democratic state Sen. Adelard L. Brault, the senior member of the Northern Virginia delegation to the Virginia General Assembly. Brault's support will be crucial to the selection since the judgeship will be filled by the state legislature next month.

While Brault would not comment on whether Fitzpatrick is his first choice for one of the$54,000-a-year judgeships, he made clear in an interview that he will push for the apppointment of a woman.

"I have made it known generally that in the 1982 session we would elect a woman to the bench," said Brault. "I think the time has come when there should be a woman on the circuit court in Virginia."

The absence of women on the state and federal benches in Virginia has been a politicial issue. Two years ago, when President Carter was pushing for appointment of blacks and women to federal judgeships in the state, judicial nominating panels created by Sen. Harry F. Byrd Jr. (I-Va.) complained that the absence of women on the state's circuit court bench accounted for their inability to find any women nominees.

Brault, a Fairfax City lawyer, said that while he wanted to see a woman named to the court, he would only support an experienced candidate, preferably a woman who has served as a judge.

Members of the Fairfax Bar will meet soon to nominate candidates for the legislature to consider. Although there is now only one Fairfax County Circuit Court vacancy -- created when Judge James C. Cacheris was elevated to a new federal judgeship in Alexandria -- the State Judicial Council has recommended that the legislature create two additional state judgeships in Fairfax. Arthur L. Moshos, Fairfax Bar Association president, said it is likely that the General Assembly will go along with the council's recommendation and approve the judgeships, giving the Democratic-controlled legislature three positions to fill.

Brault and Fairfax court officials say it is unlikely that more than one woman will be elected to the bench this year, even if the circuit court is expanded from nine to 11 judges.

There is currently only one other woman judge sitting on a lower court in Fairfax County. Barbara M. Keenan, 31, a judge in the Fairfax County General District Court. She is also seeking the nomination to the circuit court, according to court officials.

"I think both women are serving with distinction now," said one county judge who did not wish to be identified. "But I think experience will be the critical factor in the decision," he said, noting that that Fitzpatrick is older and has served longer on the bench.

Fitzpatrick, a native of Birmingham and a graduate of Tufts University, earned her law degree from Catholic University. She joined the Fairfax Legal Aid Society as an attorney in 1974 -- her first position in the legal profession. Her husband, Charles H. Fitzpatrick, also a lawyer, worked nine years for Rep. G. William Whitehurst (R-Va.) until he joined the Robb campaign, where he spent three months as a campaign spokesman.

Johanna Fitzpatrick was first named a substitute judge in 1979 and was elected a full-time judge by the legislature the following year.