A Reagan administration effort to bring about Arab-Israeli peace talks, initially through a Middle East peace conference, is to begin this weekend as Assistant Secretary of State Richard W. Murphy travels to several countries in the region, State Department officials said yesterday.

The department's senior Mideast expert served as diplomatic troubleshooter on six trips to the area last year.

His current travels are notable for a new emphasis on arranging an international conference, which would include representatives of the Soviet Union, as a formal convening authority for Arab-Israeli talks.

The United States and Israel have been unenthusiastic about such a conference, partly because of resistance to Soviet involvement.

But Israeli Prime Minister Shimon Peres has been moving in recent months toward acceptance of such an "international forum" for peace talks, and the Reagan administration, through Murphy's trip, has decided to examine more closely the possibility of convening such a meeting.

Israel's attitude toward an international conference has hinged largely on improvements in the Soviet posture toward Israel, including the prospect of renewed diplomatic relations between Moscow and Jerusalem and an increase in Jewish emigration from the Soviet Union.

The Soviets are showing signs of increasing interest in Israel although no definite steps are expected before the important Soviet Communist Party congress in late February, at the earliest.

King Hussein of Jordan, whose assistance is considered crucial in a potential Mideast peace process, has insisted for months on an international conference to authorize direct negotiations of a joint Jordanian-Palestinian delegation with the Israeli government.

Hussein met Syrian President Hafez Assad, another important figure in Mideast diplomacy, in Damascus last Dec. 30-31, ending a year widely but prematurely billed as the one in which serious Mideast peace negotiations were to resume.

State Department sources said that Assad's private position on an Arab-Israeli peace conference and negotiations remains unclear but that they detected no lessening in Hussein's interest in moving ahead.

One of the greatest uncertainties is the potential role in peace negotiations of the Palestine Liberation Organization and its chairman, Yasser Arafat.

According to a well-informed State Department official, Hussein may be forced to choose between cooperation with Arafat or Assad, who are bitter enemies.

Secretary of State George P. Shultz is reported by aides to be determined that any international peace conference have a strictly limited role and specifically not be empowered to intervene in or reject results of direct Arab-Israeli negotiations that might take place under its general auspices.

The specific powers of a Mideast peace conference are expected to be among central topics of Murphy's explorations in Israel, Jordan and perhaps other countries.

Another key question for Murphy will be how Palestinians should be represented, a knotty problem often addressed last year but never solved.