Abstract: With the rapid development of science and technology in recent years, libraries need to annotate and mine collection resource to provide users with high-quality knowledge and information. Based on the analysis of the meaning and characteristics of big data technology, this paper analyzed the impact of big data technology on the library construction, including library service model, data mining, knowledge information tagging, knowledge information discovery system, and discussed the advantages and functions of knowledge annotation and mining of library collection resource in big data era, including citation analysis, function description, semantic relevance orientation, academic source of content discussion, and summed up the construction approach of knowledge annotation and mining mechanism.