Li Zhengdao is a Chinese American physicist. Though born in Shanghai, Li is a native of Suzhou, Jiangsu Province. From 1944 to 1946, he studied at the Department of Physics first at Zhejiang University and then at National South-West Associated University. He received his doctorate degree from the University of Chicago in 1950. In 1956, Li jointed Columbia University as a professor. In 1960, he became a professor of the Institute for Advanced Study in Princeton, N. J., USA. From 1964 to present, he has been appointed as an Enrico Fermi Professor at Columbia University. From 1984 to present, he has been a full professor at Columbia University. Li is an academician of the American Academy of Arts and Sciences, the National Academy of Sciences in USA, and a foreign academician of the Academia Linceorum in Italy. From the late 1940s to the early 1970s, Li made important achievements in researches on weak interactions, concerning such issues as two-component neutrino theory, universality of weak interactions, the theory of intermediate bosons and CP violation in neutral kaon decay. In the field of statistical mechanics, Li collaborated with Yang Zhenning as well as other scholars and made groundbreaking contributions to many-body theory. He developed the theory of non-topological solution and harden models during the 1970s and 1980s. It is he who introduced important concepts such as the “Lee model,” “KLN theorem,” and “anomalous nuclear states” in theories concerning quantum field. In 1956, the epoch-making discovery of the law of parity non-conservation in weak interactions was discovered and later confirmed by Chien-Shiung Wu’s experiments. The year of 1957 witnessed Li and Yang Zhenning jointly honored with the Nobel Prize for physics. In 1994, Li was elected as one of the first foreign academicians of the Chinese Academy of Sciences.