William Clohan, who was fired last week as number two man at the Department of Education, described himself yesterday as a victim of the Reagan administration's right wing and conservative pressure groups from outside the government.

Clohan, the former undersecretary of education, also told reporters in his first public statement since his dismissal that he believes the Education Department has "more than its share" of far right political appointees because conservative groups have made a target of the federal role in education.

Several education lobbyists said at the time of the firing that they viewed it as an effort to purge the department for ideological reasons. And Clohan said, "Perhaps there was feeling they needed to respond to pressure from the extreme right wing."

The 33-year-old Clohan said he agreed that the president has a right to fire his appointees, but said he was upset by the abruptness of the action.

He was "being watched very closely" in recent months because some Reagan officials were "suspicious" of his ties to Congress, where he worked as a Republican aide to the House Education and Labor Committee. There was some concern that he might not work hard enough to alter many of the laws he had helped draft, he said.

Clohan said the timing of the dismissal surprised him. Secretary of Education Terrel H. Bell returned from a White House meeting with personnel chief E. Pendleton James last Wednesday and told him he had to be out of his office by nightfall, he said.

"No reason was given. The implication was they didn't have confidence in me . . . . It was unsettling. I would feel much better if they gave me a good reason," he said during the session in his home in southwest Washington.

His recent comments about the tuition tax credit plan the president is expected to announce Thursday seemed to "trigger" the firing, he said. Edwin Meese III, one of Reagan's top aides, reportedly called Bell the same morning the story appeared and was upset about what Clohan had said, which was only that the broad outlines of the proposal had been approved.

Clohan said he doesn't think the tuition tax credit plan will be enacted this year because of budgetary restraints. "Let's say it's reported out and gets defeated. It's possible Congress will set it aside for many years to come."

Clohan said he had dissented in some internal policy-making discussions, but said he always backed the administration's final decision in public. "If being a team player means being a yes man, I wasn't a yes man."

He said at one point, with a laugh, that his departure might actually quicken the decision-making pace at the department because, as a lawyer, he asks a lot of questions.

Clohan said he doesn't have any definite plans yet, although he said he doubted he would return to work in Congress.