Finally overcoming its concern about Soviet displeasure, Japan sat down at the negotiating table with China yesterday to work out a long-delayed peace treaty.

Preliminary negotiations opened in Peking yesterday afternoon for the "peace and friendship" treaty first proposed six years ago. It has been shelved since 1975 because of Soviet objections.

If it is ever drafted and signed, it will be a work of diplomatic artfulness because the two countries disagree on a major point, the Soviet role in Asia.

The Chinese want the treaty to include a clause declaring the two parties opposed to the dominance in Asia of any third country. The Soviet Union, knowing that such a clause is directed against it, has denounced the idea and warned Japan not to accept it.

Japan, which wants to keep peaceful relations with the Soviets while moving still closer to China, has tried to straddle the fence by saying it will agree to the so-called "anti-hegemony clause" if it can also somehow declare that clause is not aimed against the Soviet Union or any specific country.

It remains to be seen how those conflicting statements can be put on a single piece of paper. Foreign Minister Sunzo Sonoda is scheduled to fly to Peking next week to participate in the delicate drafting work.

The peace treaty was proposed in 1972, when Japan normalized its relations with China. Negotiations were interrupted in 1975, however, after the Soviet Union strongly objected to the anti-hegemony clause, insisting that it would regard such a declaration as an unfriendly act by Japan.

Prime Minister Takeo Fukuda's ambivalence on the issue has been the main obstacle to resuming the talks and one of Tokyo's biggest guessing of whether Fukuda really wants to sign the pact.

He has said he wants an early agreement. He also has said China must understand Japan's positions, which is that the anti-hegemony clause should not be aimed at any specific country. Japan's foreign policy, he has said, is based on being friendly with every country in the world.

Domestic politics seems to play a large part in Fukuda's thinking. The prime minister recently showed a visitor a public opinion poll which indicated that only about 20 percent of the Japanese believe an agreement should be accepted unconditionally. The visitor said Fukuda interpreted that to mean there is overwhelming opposition to any agreement which violates Japan's policy of being friends with everyone.

The visitor's impression was that Fukuda could turn in either direction.

Yet Fukuda is also said to feel that signing of an acceptable pact would be a big plus for him in the election that will take place in December. His main adversary in the ruling Liberal Democratic Party, Secretary General Masayohi Ohira, favors an agreement and he could be in a position to blame Fukuda for ineptness if one is not signed.

The other main pressure for an agreement has come from Japan's business community which is eager to solidify relations with China to increase trade. Earlier this year, the two countries signed a major long-term trade agreement, under which Japan will sell large quantities of steel to China and import crude oil in return.