It was almost like the good old days, said Mike Tillman, veteran student radical, as he gazed out across the campus of the University of Maryland from his porch on the administration building steps.

"I remember when there was a policeman at every corner," he said nostalgically. "This was a real storm center. Students saw what the ruling class was doing to the country."

For a brief moment yesterday, those by-gone days of the '60s returned to the College Park campus. In what was almost a quaint reminder of another age, Tillman, 25, a member of the Revolutionary Student Brigade, and six other young people seized the office of the chancellor of the university.

The move had all the trappings of the old student protest movement. One of the young people carried a bullhorn to rally troops. Another hastily unfurled a hard-to-read banner from the chancellor's window. Still another breathlessly telephoned the news media while a reporter from the campus radio station recorded it all from inside the office of the chancellor, Dr. Robert Gluckstern.

Tillman, wearing the worn denim jacket, the work boots, and the blue-jean uniform of the '60s, later recounted the scene: "We walked in (the office). He (Gluckstern) said, 'Whate do you want?' We told him our demands and said we wanted to talk about them. He got up and called the police. We barricaded the door."

"I'd say he was a little upset," said Tillman, a university sophomore. "It kind of broke his ability not to deal with the real issues."

But there was something very different about the demonstration from those of the late 1960s and early 1970s.

First, it lasted only about 45 minutes, and involved only a handful of students. The banner and bullhorn outside the chancellor's office attracted a noontime crowd that observers said never numbered above 75. The demonstrators left the office when they were warned they might be arrested. They left at 12:25 p.m. almost an hour before the first - and only - TV camera arrived.

Secondly, the university took it all almost casually. "It just shows what two days of nice spring weather will do," said Patrick Hunt, director of university relations. "The old protest phenomena has passed. Maybe these youngsters are trying to get their battle stars."

Campus police made no arrest. The two nonstudents involved were given trespassing citations. The question of what to do with the students involved was referred to the campus judicial board.

Chancellor Gluckstern agreed to meet with representatives of the protest group next Monday to discuss their two demands: that the university divest itself of $1.5 million in holdings in companies that deal with South Africa, and that Edward V. Hurley be reappointed to the university's board of regents. Hurley is an outspoken black, who along with former Sen. Joseph Tydings raised the South African investment question before the board. Gov. Marvin Mandel failed to renew Hurley's appointment last week, and he is to lose his seat this June.

Tillman and other members of the Revoluntionary Student Brigade, a small campus "Marxist" group, declared the demonstrations a success. "It made the question of university investment in South Africa a very burning issue," he said, as he sat alone on the administration building steps.

The student protest movement is not over, he insisted. "We're in what I'd call a lull . . . Students are caught in a real bind. The economy is in such a terrible shape. Jobs are really hard to find. This means students have to try harder in school, and step on one another to get ahead. They're more careful than they once were."

Actually, protest demonstrations never completely disappeared from the College Park campus. They just got smaller, futher apart, and the press began ignoring them, observers note.

Last April 7, for instance, 500 students marched on the campus mall, and a smaller group charged into the office of Thomas B. Day, a vice chancellor, to protest university policies toward a campus food co-op. And last fall a group of demonstrators buried a coffin titled "student apathy" on campus.

Adam Pertman, editor-in-chief of The Diamondback, the students newspaper, said neither these demonstrations nor yesterday's protest are indicative of any change in mood on campus.

"Apathy is still alive and well at College Park and probably growing," he said."Demonstrations are just part of spring," said another student, Joe Calderone. "You wouldn't get something like this happening in the middle of winter."