 In 1979, Li joined the newly-founded Institute of Marxism–Leninism at the Chinese Academy of Social Sciences(CASS), where she researched on marriage and the family.After obtaining the doctorate degree from the University of Pittsburgh and returning to China, Li worked as a post-doctoral fellow under the acclaimed sociologist Fei Xiaotong, then an instructor at Peking University.In 1992 she joined the Institute of Sociology at CASS as a researcher, and later the director of the Research Office of Family and Sexuality.