A group of 800 Howard University students marched on the school's administration building yesterday demanding that the university reinstate the editor of the student newspaper by Friday or face student reprisals.

The students called the protest in support of Janice McKnight, a Howard senior and editor of The Hilltop since April, who was expelled Tuesday because, university officials said, she provided "untruthful" information on her 1979 admissions application. Her dismissal followed a campus controversy over the paper's coverage of a sex discrimination complaint against the school.

The university also released yesterday a Jan. 28 letter officials sent to McKnight detailing their allegations. Carl Anderson, university vice president for student affairs, said that McKnight was given an opportunity to discuss the matter and respond by Tuesday noon, but did not do so.

She was subsequently expelled and dismissed as the editor.

John Clifford, McKnight's attorney, said that McKnight sent a letter to the school Tuesday promising a full explanation by Feb. 14. Clifford said that despite the letter, she was still dismissed.

"This is obviously a pretext because the university would never come out and say they are canning her because she printed the story," Clifford said. "They had to find a reason to dismiss her and this was it."

Under the school's rules, omitting important information or falsifying information on admissions applications is grounds for dismissal. There are no procedures for reinstating an expelled student, Anderson said.

Anderson said the school reviewed McKnight's records while trying to determine "what could be done" about The Hilltop's handling of controversial and potentially libelous stories.

"On Miss McKnight's application for editorship of the student paper, she stated she had had a year's experience on a student newspaper at Syracuse University," Anderson said. He said officials compared that application to her entrance application and discovered that she had not come to Howard from a District high school, as the admissions application indicated, but that she had spent a year at Syracuse University and left in 1979 in poor academic standing.

During the noon demonstration yesterday, Howard Newell, president of Howard's undergraduate student government, told chanting students that the main reason McKnight was dismissed from the university was that she continued coverage of the controversial sex discrimination complaint after Howard President James E. Cheek told her not to give the case prominent coverage.

The crowd, estimated by students and officials at 800, marched through the campus to the school's administrative offices shouting such slogans as "We want Cheek out!" and waving banners, one of which said: "Freedom of Speech Is Dead at Howard University."

Once the crowd reached the administration building, Newell said McKnight was denied due process and demanded, among other things, that she be reinstated. Then he led about 200 students to the fourth floor of the building to Cheek's office, where they demanded to see him. University officials said later that Cheek did not come to work.

After waiting to see Cheek for about an hour, the students disbanded peacefully.

"We will protest every day until Cheek reinstates Janice McKnight," Newell said, to the cheers of the students.

The students demanded a meeting with Cheek at noon Monday to discuss McKnight's case and other student concerns. They also demanded that McKnight be reinstated by Friday or the students would close the university. Anderson said the school could not respond until it received the students' demands in some formal fashion.