About 25 people, members of a new student organization called the Committee for Worker-Student Unity, picketed for an hour yesterday in Holyoke Center in support of a dining hall worker who is trying to have two warnings cleared from his record.

The students, holding signs and chanting slogans, marched in the Holyoke arcade in front of the University Information Office. They held the demonstration because they thought a hearing on the worker's case was going on in the Personnel Office, on Holyoke Center's sixth floor.

The worker, Sherman Holcomb, was in the Personnel Office, but for another reason. Holcomb is shop steward of the Radcliffe dining hall workers, and had gone to the office for a hearing on another worker's grievance.

Holcomb is trying to remove from his record warnings charging him with excessive absenteeism and with disrupting a workers' meeting, charges he denies.

A spokesman for the student group, who would not give her name, said, "It's part of the University's overall policy to try to break up union organizing."

The demonstration ended when University policy told the students to turn off their megaphone because they were disturbing patients in the University Health Services.

Edward W. Powers, director of employee relations, said yesterday the hearing on Holcomb's case will take place after the completion of a preliminary investigation on part of Holcomb's complaint against the University.

That part calls for the firing of Holcomb's superior, Frances E. Sweeney, dining hall manager at Moors Hall, for her alleged harassment of Holcomb.

Asked to comment on the demonstration, Powers said. "There's an awful lot of confusion about this because of the way the shop stewards are handling things."

Holcomb said yesterday he is "proud about the students being there, that I got a reaction."

William Lee, equal employment opportunity officer in the Department of Buildings and Grounds, is investigating whether Sweeney should be fired. Only when he comes to a decision can the rest of Holcomb's hearing proceed under the auspices of the Personnel Office, probably not starting for several weeks.