BEIJING, AUG. 12 -- A leading Chinese Communist Party theoretician is under attack and will be fired from his position because his views depart radically from current party orthodoxy, according to Chinese sources.

The sources said that Su Shaozhi, 63, director of the Institute of Marxism-Leninism and Mao Tse-tung Thought, has offended party leaders with his criticism of the Chinese political system and his advocacy of democratic reforms.

They said that high-level officials made a decision to dismiss the theoretician more than two weeks ago.

The sources said that at least three other intellectuals were being forced to resign from the Communist Party, including liberal theorist Wang Ruoshui and a prominent and outspoken playwright, Wu Zuguang. Wu, 70, confirmed that party officials had advised him to resign from the party and that he did so on Aug. 1.

One source said that several other "liberals" were likely to be forced out of the party in the future.

Independent analysts said that the country's top leader, Deng Xiaoping, was likely to have approved the moves as part of a compromise with party traditionalists, or conservatives.

In order to push their economic reforms, Deng and acting Communist Party Secretary Zhao Ziyang have been willing to make certain concessions to the conservatives in the ideological field.

Trade-offs are expected to occur between party reformers and conservatives at a major party congress, scheduled to be held in October. One Chinese who was aware of the move to oust Su said he was shocked that the decision was timed so closely to the party congress, which is expected to stress unity.

Sources said that the removal of Su would be done quietly, without a formal announcement, to avoid alarming Chinese intellectuals whose talents are regarded as crucial to modernization.

But Deng has agreed with the conservatives that intellectuals went too far during a debate over possible political reforms. Su Shaozhi had called for restrictions on the enormous power of the Communist Party and a gradual democratization of the country.

Su, who was readily available for interviews last year, stopped seeing foreign journalists in January after university students launched demonstrations calling for democracy.

Reached by telephone today, Su said he could not comment on reports that he was being pressured to resign. A spokesman for the Chinese Academy of Social Sciences said, "We haven't heard anything like that."

Zhao Ziyang has tried to assure intellectuals that a campaign launched earlier this year against "bourgeois liberalism," or western influences, was limited in scope and would affect only a few party members. The campaign resulted in the much publicized ouster of three prominent intellectuals from the party.

Su's research institute was established in 1979, under the Academy of Social Sciences, to study Marxism and the thought of the late party chairman Mao Tse-tung. The Communist Party had previously regarded the thoughts of Mao as too sacred to be open to study and debate.

The institute has no political power, but it has been influential in reinterpreting Marxism and proposing political reforms.

According to Chinese sources, orthodox Marxists attempted to abolish the 100-member institute in 1983.

Su came under criticism at that time but later said that he refused to make any compromise with his critics.

Su shared the view of former Communist Party chief Hu Yaobang that the writings of Marx and Lenin cannot be expected to solve all of China's present-day problems. He attacked dogmatism and advocated "creatively applying and developing Marxism" with the ultimate aim of promoting economic productivity.

According to the theoretician, the traditional Marxist view that manual laborers should lead the rest of society was out of date.

In an interview last year, Su said, "In the future informatics society, the main workers will be mental workers, and intellectuals will be the main center for producing value."

During the Cultural Revolution of 1966-1976, Su was called a "rightist" and sent to work as a cook in the countryside for 2 1/2 years.