A D.C. Superior Court judge ruled yesterday that Howard University may expel student newspaper editor Janice McKnight, at least until a trial of her lawsuit seeking reinstatement as a student and editor is held. But university President James Cheek said later that he has decided to let McKnight remain a student.

The day's developments left unanswered whether McKnight would be allowed to remain as editor of The Hilltop, the student newspaper. Cheek said her future with the newspaper would be determined later by a policy board made up of student leaders, administrators and faculty members.

The Hilltop's articles about a sex discrimination complaint against the university and the school's subsequent decision--now reversed--to expel McKnight touched off a series of student protests in recent weeks against the school's administration.

Attorneys for McKnight said they would appeal yesterday's ruling by Judge Sylvia Bacon and immediately filed a request for a court order extending McKnight's temporary reinstatement until the matter could be taken up by the D.C. Court of Appeals.

However, Cheek's statement settled the question of McKnight's reinstatement as a student. "In the interest of all parties concerned, I have decided that Miss Janice McKnight will be permitted to remain as a student at Howard University," Cheek said.

The action came less than a week before Howard's annual Charter Day convocation, scheduled for Wednesday, which in the past has been a target of student demonstrations.

The university's initial decision on Feb. 1 to expel McKnight for allegedly misrepresenting her academic background on her 1979 admissions application had been held in check since Feb. 8, when a court order reinstated her pending yesterday's hearing.

University officials said that an examination of McKnight's records showed that she had failed to note on her admissions application that she had previously attended Syracuse University and left that school "not in good standing."

The university's discovery came after a dispute between McKnight and school officials over The Hilltop's coverage of a sex-discrimination complaint against the university's general counsel.

McKnight continued to publish articles about the case despite urgings by Cheek that the paper stop writing about it.

McKnight, a 23-year-old senior from Northeast Washington, sued the university, arguing that her expulsion was a retaliation for her editorial policies and that her First Amendment rights had been violated.

In her opinion yesterday, Judge Bacon denied McKnight's request for a preliminary injunction that would have barred the university from expelling her until the dispute was settled in court. Bacon ruled that McKnight had failed to show that she would likely win her case or that she would suffer "irreparable harm" if the injunction were denied.

Bacon wrote that McKnight's contract as a student "is voidable" because of "her own material misrepresentations on her application for admission . . .

"While it may well be that Howard University has not been perfect in its conduct in this matter," Bacon wrote, it is McKnight's "failure to disclose which is a major factor in persuading the court that she is not entitled to relief before trial."

The dispute arose after a staff lawyer, Michael Harris, complained that university general counsel Dorsey Lane favored female employes in pay and promotions. McKnight gave prominent coverage to the story and eventually printed an editorial calling for Lane's resignation.

In her court papers, McKnight said Cheek met with her twice in his office and asked her not to print anything more about the case, saying that the paper might lose university funds if the articles continued.

Michael Harris was fired Jan. 31. McKnight was expelled the next day.