As the enormous progressing of information society and information technology, the library paradigm shifts dramatically. Librarians need to have more proper competencies to achieve new missions and meet the challenge. This study is to discuss the competencies for academic librarians of the 21st century in Taiwan and was conducted by literature review, focus group, and survey of the academic librarians in Taiwan. A competency list for the academic librarians in 21st century was drafted up by literature review. In order to generate a localized competency list, two focus group meetings were held. This missions, roles, job scope, and competencies of the academic librarians were ascertained and discussed in the focus group meetings. These results guided and modified questionnaire to generate a core competency list for academic librarians. The questionnaires were finally distributed to all academic librarians in Taiwan. At of the 1,134 surveyed questionnaires of 105 university and college libraries, 873 responded and 854 validated. And the overall findings were highly consistent with the main categories and definitions of the study in library missions, roles, job scope, and competencies. More discussion and suggestions were submitted.