U.S. Ambassador to El Salvador Thomas R. Pickering will be moved to another major post in the next few months because of continued concerns for his safety in Central America, State Department officials said yesterday.

His transfer would be one of several dozen ambassadorial changes anticipated as the Reagan administration begins its second term, according to the officials, who declined to be identified.

They said the majority of the shifts would occur in Africa and Latin America, some for political reasons and some -- as in Pickering's case -- for special reasons, but most routine.

Pickering, 53, a widely respected career diplomat, has been threatened with death at least three times during his 16 months in El Salvador, allegedly by right-wing groups critical of U.S. support for land reform and for President Jose Napoleon Duarte. One of the threats allegedly was going to be carried out in the United States, and Pickering has been under special 24-hour guard since it was made.

He reportedly will be succeeded by Edwin G. Corr, currently ambassador to Bolivia; Corr has led the U.S. effort to halt drug traffic out of that country.

Other changes, the officials said, could involve ambassadors John Negroponte in Honduras, Curtin Winsor in Costa Rica, James Theberge in Chile and Lewis Tambs in Colombia.

Assistant secretary of state for Western Hemisphere affairs Langhorne A. (Tony) Motley said any changes would be part of "an ongoing requirement for rotations that have been backlogged since last June." He would not confirm or deny particular shifts.

White House spokesman Robert Sims added that if there were shifts, they would not represent any change in U.S. policy toward the countries involved. They are "normal proceedings of changes of posts at the start of a new administration," he said.