Based on literature review and comparative study,this article expounds and proves the core contents of the Library and Information Science(LIS) from three aspects:history,status quo,and comparison with related disciplines.Disclose,evaluation,organization and uses of knowledge are core contents from the aspect of the relationship between document & knowledge and information & knowledge.The development of secondary and tertiary publications,subject databases,reviews and newsletters are its core contents in terms of the extent of literature organization.Analysis,evaluation,uses and effectiveness of knowledge contents are its core contents in terms of the formation,content and effectiveness of knowledge.Knowledge and people are its core contents from the perspective of the four elements that constitute the information,knowledge,and intelligent systems.Based on the core contents,solutions for core curriculum,professional training and development of the discipline and the cause of LIS are proposed. Based on literature review and comparative study, this article expounds and proves the core contents of the Library and Information Science (LIS) from three aspects: history, status quo, and comparison with related disciplines. Disclose, evaluation, organization and uses of knowledge are core contents from the aspect of the relationship between document & knowledge and information & knowledge. the development of secondary and tertiary publications, subject databases, reviews and newsletters are its core contents in terms of the extent of literature organization. Analysis, evaluation, uses and effectiveness of knowledge contents are its core contents in terms of the formation, content and effectiveness of knowledge.Knowledge and people are its core contents from the perspective of the four elements that constitute the information, knowledge, and intelligent systems.Based on the core contents , solutions for core curriculum, professional training and development of the discipline and the cause of LIS are pr oposed.