Chinese leaders have indicated that they will resume purchases of U. S. grain after a two-year absence from the glutted American wheat market, the head of a key SIno-American trade group said today.

Christopher H. Phillips, president of the National Council for U.S. China Trade, said Chinese trade officials told him grain was back on the list of item Peking "may" buy from the United States. The Chinese used the same language in the past to signal that turned out to be major purchases of polyester fibers, lumber products and other goods. Phillips said he thinks the Chinese statement means China will buy American grain in the near future.

The Chinese have already contaracted for delivery of about 7 million metric tons of wheat from Canada, Australia and Argentina in 1977. their largest grain imports since 1974. U.S. trade experts have been led to believe that the Chinese fear that strikes and other dockside delays may slow deliveries from Canada.

Peking could not choose a better time to buy American grain, for U.S. wheat prices are at a five-year low afater four years of huge harvests. When American trade with the People's Republic of China began in the early 1970s. China quickly bought about 8 million metric tons of U.S. grain. But a Chinese foreign exchange deficit and severe politaical difficulties brought an end to purchases of U.S. wheat after 1974.

Arriving here after a visit to Peking and other Chinese cities, Phillips said the Chinese had promised to buy more of U.S. goods in the latter gart of this year. They said the amount of the increased trade would depend on how far the Carter administration moved toward formal diplomatic recognition of Peking.

"You cannot separate politics from economics." Phillips quoted Wang Yeo-ting, chairman of the China Council for the Promotion of International Trade, as saying.

Phillips, who has been to China several times, said he was given a particularly warm welcome in Peking Wang and Foreign Trade Minister Li Chiang greeted him the minute he stepped off the airplane and repeatedly expressed hopes for full normalization of U.S.-China relations.

Phillips, a former deputy U.S. ambassador to the United Nations, heads an association of American corporations that is recognized by both China and the United States as the principal U.S. agent for commercial contacts between the two countries. Businessmen belonging to the council have received unusually coradial treatment from the Chinese, who see them as key allies in their effort to win full diplomatic recognition from Washington.

Phillips personally favors normalization of relations and said he has been invited to testify at congressional hearings on U.S.-China relations later this month. He said he thought Congress should "get the message" about the long-range advantages in trade and diplomacy that would grow out of recognition of Peking.

Experts on Chinese agriculture say Peking wants to buy more grain now to replenish reserves depleted by bad harvests in areas hit by political turmoil last year and by drought this year.

There are reports that the Chinese have begun to purchase U.S. cotton again and are showing renewed interest in U.S. oil equipment. Phillips said a iteam of Chinese oil experts now touring the United States under the sponsorship of the council will visit the Alaskan oil pipeline, a sign that the chinese may wish to purchase American pipe for their own mushrooming oil industry.

Phillips said he saw signs of a new pragmatism in Chinese economic policy during his trip. One factory manager told him that the government had decided on a long-overdue wage increase for workers, although the policy hadn't been implemented yet.d yet.