Finding itself increasingly isolated as foreign diplomats here pack up and move to Peking; this last bastion of Chinese anti-communism has stumbled across a unique way to win friends abroad - borrow their money.

Making a virtue out of the need for foreign help in keeping a mineral poor islands economy alive, the Nationalist Chinese leaders of Taiwan have incurred estimated foreign debts of nearly $4 billion.

Most of that is owed to American financial institutions, who have become some of the strongest backers for continued U.S. resistance to China's plans to liberate Taiwan.

Especially since the 1972 Shanghai communique raised the prospect of an end to U.S. diplomatic relations with Taiwan for the first time, the Nationalist government here has actively wooed American bankers. Twelve U.S. banks now have branches or representative offices here, "most of them set tip in the last three or four years," said Thomas E. LaMonica, manager of the long-established Chase Manhattan Bank branch here.

The government's Industrial Devel-Department has been particularly attentive to regional U.S. banks like the Republic National Bank of Dallas, seeking to strengthen Taiwan's ties with influential leaders of the American Midwest and other regions.

The government's Industrial Development and Investment Center has recently opened offices in Chicago and Los Angeles to seek more direct investment for heavy industries Taiwan now wants to promote.

T. Y. [WORD ILLEGIBLE], the center's deputy director here, said such promotion efforts had no immediate diplomatic purpose, "but in winning investment from the investors, you win the friendship of the investors and it helps our diplomatic relations with your good country."

The effort has impressed even the more outspoken Taiwanese here who have been critical of the government, still run largely by men born on the mainland, for its alleged neglect of Taiwan's future in favor of pursuing the dream of recapturing all of China.

"They're not as stupid as they appear," said one Taiwanese politician. "They are boosting their economic and trade staffs in nations with which they no longer have relations."

"It's impossible to say that government economic policies are made without some political motives behind them," Lamonica said.

Perhaps in part because they realize that Taiwan's extensive borrowing is an effective political weapon, Chinese leaders in Peking have given Taiwan Premier Chiang Ching-kuo's foreign debt policy special attention in their ongoing propaganda war.

"The Ching gang has begged for huge foreign loans and provided foreign monopoly capital with every convenience to plunder and control the Taiwan economy, opening up Taiwan's economy to greater foreign penetration and colonization," said one dispatch from Peking's New China News Agency.

Asked how he reacts to such charges. Taiwan's Economic Affairs Ministry Y. S. Sun said, "I laugh. They don't know what they are talking about. They are still telling people on the mainland that people in Taiwan are short of food and must eat banana peels."

"We feel that basically foreign investment brings with it not only capital but also technical knowhow . . . We learn from this. Saying this should affect the autonomy of a country is silly," Sun said.

"Basically since we moved to Taiwan, we have adopted a policy of an open economy," Sun said. "Our island is so small and our resources so limited, that we have to be a cooperative member of the international community. We welcome foreign investment, we promote foreign trade."

Still, the island's reliance on friends abroad has bothered the Nationalist Chinese. Since the 1972 Shanghai communique threatened their U.S. ties, they have embarked on a massive program of capital improvements to strengthen their home-grown economy.

Called the "Ten Great Construction Projects," the $7 billion program has required at least $3 billion in foreign funding. When it is completed in a few years, the island will have improved harbor, highway, rail and airport facilities, an integrated steel mill and a new petrochemical complex.

The program will also provide three nuclear power plants at a cost of $2.5 billion that will save $400 million a year in foreign exchange earnings now spent to import Middle East oil.

Taiwan leaders like Sun acknowledge how much the island's survival depends on the borrowing program's ability both to win friends overseas and bring more economic self-sufficiency. In the past few years the island has watched as Japan and all the remaining friendly governments of Europe moved their diplomats to Peking. Only a few Latin American and African nations, plus the vitally important United States and Saudi Arabia, still recognize the Taipei government.

Taiwan has won new friends in the financial world through skillful, conservative management of the economy that has brought foreign exchange reserves by some estimates to almost $4 billion. The Gross National Product increased nearly 12 per cent to $17 billion last year, and it is expected to grow another 3 per cent this year.

Low labor costs - which some critics attribute to the martial law restraints against strikes - and low inflation encourage investment. What financial experts describe as a world-wide slow-down in direct investment has affected some Taiwan industries this year, however, and economic planners here continue to worry about the political future.

"Ever since 1971, when we withdrew from the United Nations (shortly after Peking was admitted), we've been confronted with the problem of how to maintain dynamic economic growth against adversities in the international scene," Sun said.

"We've gained some experience, but on the other hand I would not say that ours is an easy job, and the situation may become more difficult with the Communist bloc getting stronger."

In perhaps the frankest official assessment to date of what trouble Taiwan would face if Washington recognized Peking. Sun said, "It is a dangerous assumption to say that the Republic of China performance has been so good for the past seven years that further change in the international scene will not affect our future performance. It is our responsibility go prepare for every eventuality."

The psychological impact of the possible closing of the U.S. embassy here "is very difficult to evaluate, its effect both on us and on other countries," Sun said. "The Communists are trying to put pressure on other countries to cut off trade with us and this may get worse."

"I hope the American people will recognize the importance of the situation and not hurt the interests between our two countries," he said.