Former Secretary of State Henry A. Kissinger has accepted a one-year appointment as a professor in Georgetown University's School of Foreign Service, reliable sources said yesterday.

Kissinger will be a full-time faculty member, according to the sources, and he will teach courses in "international diplomacy." The appointment is expected to be announced sometime next week.

Kissinger was reported to have recently rejected an offer from Columbia University that he fill an endowed chair there in political science. There was intense student opposition to his appointment at Columbia because of Kissinger's role in shaping controversial U.S. policy on Chile and Vietnam and in the wiretapping of government aides suspected of leaking information to the press.

Aside from Columbia, Kissinger was reported to have had offers from Yale, the University of Pennsylvania, New York University ad Harvard, where he made his reputation before entering government service.

One source said that Kissinger, who's still living in Washington, was persuaded to take the Georgetown post because he would not have to commute. The public and private papers he needs to write his memoirs, for which Little, Brown has reportedly paid about $2 million, are all in Washington.

Kissinger currently has a position at Georgetown's Center for Strategic and International Studies and lectures from time to time in the foreign service school. His salary for the six months' job which began March 1, is about $15,000.It is not known what Kissinger will be paid for his full-time assignment that begins in the fall.

There is no provision under the six month arrangement for Kissinger to meet with students, but he will do so regularly when he joins the foreign service faculty.

Kissinger also has a five-year contract with the National Broadcasting Co. as a special consultant on world affairs which will include on-the-air appearances.

An irony of the Kissinger appointment is that Donald Herzberg, dean of the graduate school at Georgetown, with which the foreign service school is associated is involved in a law suit against Kissinger.

Herzberg is one of a group of journalists, historians and political scientists who are suing to establish that transcripts of Kissinger's office telephone calls while he was Secretary of State are public rather than private documents and therefore belong to the country, not Kissinger.

Herzberg said yesterday that "I welcome Kissinger as a colleague, but I still think he is wrong on a lot of issues and I'm suing him."

Jock Covey, assistant to Kissinger, initially said that Georgetown has made the offer, but Kissinger had not yet accepted. Two hours later, however, he said "things had changed" and he had "no comment at his time."

Covey said that Kissinger also had no comment.