When President Reagan and six other western leaders meet next weekend at Colonial Williamsburg for the ninth annual economic summit, their ability to sidestep serious disagreements and produce what a Japanese diplomat calls a "banal success" may determine whether there will be a summit next year.

"There are few expectations at Williamsburg, except survival," said a White House aide.

He and other American officials made clear that the main objective of the advisory team for the president, who will be the summit's chairman, is a satisfactory if unspectacular result, with no obvious stumbles by Reagan.

Michael K. Deaver, deputy White House chief of staff, has arranged a tightly controlled summit, in which Reagan and the leaders of Canada, Britain, France, West Germany, Italy and Japan will deliberate in unprecedented isolation.

At two meetings and four meals, no one but the seven leaders will be present. They will wear headphones to receive translations from interpreters monitoring the discussions by television.

The leaders will be exposed to public view only for ceremonial and televised spot appearances, at which they cannot be interviewed. No member of the official parties is to give interviews while the summit is in progress. The other six leaders are expected to brief the press together at the end of the meeting, but Reagan is not scheduled to meet with reporters until he returns to Washington.

Despite considerable preparation, much of it designed to minimize conflict and mishap, the summit has been left less formally structured than previous ones. It will not have a draft communique prepared by aides for debate by the leaders. Instead, according to the White House, they are to shape their own final statement after some discussions for which they will set their own agenda.

"The president wants an unstructured summit and has pushed and pushed to see that he gets it," Deaver said. "He first raised the issue on the plane ride after last year's summit at Versailles when he said referring to debating pre-prepared statements , 'Why do the summits have to be like that?' ."

Reagan decided to change the system, Deaver said, and wrote to the other six participants to get their assent to a less formally structured approach.

"The difference between this summit and the last two is that we're not going with a pre-packaged set of agreements," said David R. Gergen, White House director of communications. "The president really wants a genuine exchange of views."

But a nervous diplomat warned: "This summit is really unpredictable. The leaders are so much on their own that you can't tell what may happen."

The Reagan administration is seeking to have the summit endorse a return to modest economic growth, coupled with a halt to growing trade protectionism. This would be an endorsement of the general agreement reached by foreign and finance ministers of a larger list of industrial nations in Paris two weeks ago at the Organization for Economic Cooperation and Development.

The idea put forward at the OECD is that the United States, Japan, West Germany and Britain should take the lead in boosting economic activity while making efforts to remove trade barriers. This is being sold as a way to help both industrialized countries and debt-ridden Third World countries.

"Economic growth is now the name of the game," Secretary of State George P. Shultz told reporters Friday. He said that the United States and some other countries represented at the summit have recently been "slipping" into protectionism, so "it will be very important at Williamsburg to get a reaffirmation of the principle of open trade."

Joining Reagan at Williamsburg for three days ending Memorial Day will be Canadian Prime Minister Pierre Trudeau, French President Francois Mitterrand, Japanese Prime Minister Yasuhiro Nakasone, West German Chancellor Helmut Kohl, lame-duck Italian Prime Minister Amintore Fanfani and British Prime Minister Margaret Thatcher, who is scheduled to cut her attendance short to continue her campaign for reelection. The president of the European Common Market also will sit in.

The seven countries' foreign and finance ministers will meet separately at Williamsburg during the summit.

Among the efforts made by U.S. officials to avoid conflict at Williamsburg is an attempt to play down the Reagan administration's desire to sharply restrict East-West trade. This was a divisive issue at Versailles last year and erupted into a bitter post-summit squabble over the Soviet natural gas pipeline to western Europe. "The U.S. is not trying to pick a fight," an administration official said.

"The East-West issue has become less controversial," Shultz said, predicting that it will be discussed quietly and unemotionally at Williamsburg. At the OECD meeting in Paris, Shultz sought to assuage European officials' fears that the United States is pushing them into "economic warfare" with the Soviet bloc, asking only that western European countries sell goods and offer loans without giving the Soviet bloc subsidies.

The biggest uncertainty for the Williamsburg summit is the willingness of Mitterrand, who as a Socialist will be ideologically isolated from the others, to confront Reagan, even at the risk of scuttling the summit process.

At the OECD meeting, Mitterrand made a surprise demand for a new "Bretton Woods" conference, designed to challenge Reagan's basic free-market belief in the virtue of floating exchange rates. Mitterrand wants the international monetary system returned to a fixed-rate basis. It is not known whether he will be satisfied with a proposal to "study" a new Bretton Woods conference.

Mitterrand also has vigorously criticized huge U.S. budget deficits, which he says lead to high interest rates and an overvalued dollar. Here, Mitterrand is articulating a view shared by the others going to Williamsburg. But they appear to have been convinced by their experience at the 1981 summit in Ottawa and last year's in Versailles that little can be accomplished by complaining to Reagan.

Reagan's answer to Mitterrand, Shultz indicated, will be to admit that his budget deficits are too high and must be reduced in the "out years" of 1985, 1986 and later. But Reagan reportedly will add that the deficit has not prevented the reduction of inflation and interest rates and maintenance of economic growth at a better level than in France.

Shultz said that he is willing to concede that it would be desirable to have "more stability in exchange markets." U.S. officials contend that such stability can be achieved if the four leading countries continue to pursue a policy combining modest growth and inflation control.

"These are ideas we're willing to talk about," Shultz said. "There are all sorts of ways to skin the cat."