中国共産党中央委員会主席
After his postgraduate work, Zheng conducted research for the Chinese Academy of Social Sciences. His theory and research focused on editing the works of Mao Zedong, Chairman of the Communist Party of China. He was later named deputy director-general of the international affairs research center at the State Council in the late 1970s. In 1988, he served as the vice-president of the Chinese Academy of Social Sciences and as the director for the academy's research institute.