French President Francois Mitterrand has rejected a Soviet proposal for a joint Franco-Soviet communique, to be issued during the visit to Paris this week by Soviet leader Mikhail Gorbachev, that would have included a denunciation of Reagan administration plans to push forward with its Strategic Defense Initiative, western diplomatic sources said here today.

Although France is the staunchest opponent of Reagan's "Star Wars" missile defense research program among the major western powers in Europe, the French "still want to avoid being used by the Soviets on the issue," a senior western diplomat said.

Gorbachev flies to Paris Wednesday with the aims of improving Soviet ties to U.S. allies in Western Europe and hardening opposition abroad to Reagan's Star Wars plans before the U.S.-Soviet summit meeting in Geneva Nov. 19-20.

The four-day trip is Gorbachev's first to a western country since becoming Communist Party general secretary in March, and the first venture to the West by a Soviet leader since 1981, when Leonid Brezhnev visited Bonn.

In Paris, French officials said today that Mitterrand would resist attempts by Gorbachev to drive a wedge between Western Europe and the United States by making a point of France's differences with the Soviet Union on nuclear weapons, Washington Post correspondent Michael Dobbs reported. Details on Page A12.

Western analysts in Moscow compare Gorbachev's Paris trip to a campaign stop in what the Soviets view as a safe district. It is designed to advertise gains the Soviet Union has made in its public relations campaign against Star Wars, to push various arms control initiatives -- including Gorbachev's proposal for a ban on nuclear weapons tests and a European zone free of chemical weapons -- and to mobilize opposition generally to the U.S. arms control positions before the Reagan-Gorbachev summit.

The Soviet press has played up the French visit, and the prospects for a positive outcome, in contrast with its coverage of the summit, which is colored with heavy criticism of the United States.

Gorbachev's visit to France apparently is also meant to call further attention to an unfolding Soviet proposal for a 50 percent reduction in U.S. and Soviet offensive missiles and bombers, including cuts in U.S. Pershings and cruises deployed in Western Europe, in exchange for Reagan scrapping his Star Wars plans. The Soviet Union is said to be in the process of presenting its proposal now in Geneva and reportedly is planning to introduce it at the ongoing superpower arms talks while Gorbachev is in Paris. Soviet Foreign Minister Eduard Shevardnadze first raised the proposal Friday in a White House meeting with Reagan.

Shevardnadze, who returned here yesterday from his first visit to the United States, will accompany Gorbachev to Paris. Also in the entourage will be: Vadim Zagladin, first deputy chief of the international affairs department of the party Central Committee; Georgi Kornienko, first deputy foreign minister; and Nikolai Komayev, first deputy minister of foreign trade.

The Paris setting also provides a ready-made prop for Gorbachev's public relation pitch, which analysts here feel is apparently tailor-made for western audiences. A taped interview to be broadcast on French television and a planned press conference with Mitterrand evidently are meant to reinforce and refresh the image of the Soviet leader projected to the public in a recent Time magazine interview.

Gorbachev's wife Raisa, who has assumed a higher profile than previous Soviet first ladies, is likely to capture cameras and public attention during her tourist-type itinerary in the French capital.

Western European diplomats in Moscow also view the Gorbachev trip as the first major test of the Soviet Union's Western European strategy since the loss of face it suffered starting in late 1983 when deployment began in Britain, West Germany and Italy of U.S. Pershing II and cruise missiles in the face of rock-hard Soviet opposition. Deployment in Belgium began earlier this year.

The visit to France is considered a backdrop for a Soviet pitch to politicians in the Netherlands, where the Dutch parliament faces a November decision on whether to ratify the cruise missile deployment. The Netherlands, the last of the five NATO allies scheduled to receive cruise missiles according to the deployment schedule, is the only one that has not yet voted to follow the dual-track decision, which envisioned deployment if negotiations failed.

Since Gorbachev came to power in March, he has fashioned a Western European policy that stresses stronger economic as well as political ties to the European Community, and stronger bilateral ties to each of the major European capitals.

So far, Moscow has failed to curry much favor in either the West German or British capitals, where government leaders favor cooperation with Star Wars research, according to western diplomats here. And Soviet attempts to fashion a more subtle appeal to Western European governments, in contrast to the earlier shrill criticism of the NATO deployments, have been confused at best, they say.

For example, Johannes Rau, vice chairman of West Germany's opposition Social Democratic Party, emerged from a recent meeting with Gorbachev to report that he assured the Soviet leader of the party's opposition to Star Wars, and that the old Soviet charge that West Germans are seeking to gain territories lost to Poland after World War II, had not surfaced in the talks.

But in its extensive report of the meeting with Rau, the Soviet news agency Tass quoted Gorbachev as calling for "the abandonment of any revanchist claims . . . . "

Moscow also surprised British officials, and chilled Anglo-Soviet relations, by responding to London's expulsion earlier this month of 31 Soviet diplomats, journalists and trade officials with the ouster of an equal number of Britons from the Soviet capital.

But Franco-Soviet relations are on a relatively upward curve, western analysts here say. Mitterrand has met with Gorbachev in Moscow. In the first six months of this year Soviet imports from France increased by 38 percent, according to French sources in Moscow, and an article in Pravda said that Soviet-French trade has doubled in the past five years.