The structure of scientific process adapting to the open science concept has been intensively changing. The libraries and librarians are to be the key actors in this process. Within the scope and differentiation of librarian and bibliographer competences for open science support, the competences may be divided into several key vectors: methodological support, analysis, and popularization of open science. While the issues of methodological support and analytics for open science have been well developed in the professional literature, the author aims at formulating the competences and assessing the readiness of new librarians for open science popularization. Based on the existing practice, the author defines the relevant skills and formulates four competences (and related knowledge and skills indicators): 1) orientation in open science trends; 2) organization of civil science activities, social partnerships and observance of legal standards in copyright, related rights, and privacy laws; 3) readiness for organizing educational events on science and civil science projects, for creating and disseminating the content to clarify the open science principle for various community groups; and 4) understanding and reproducing modern forms and methods of open science popularization. Based on the Federal State Educational Standard 51.03.06 “Library Information Activities” and academic curricula, the essential competences are formulated. The author also discusses the findings of the survey “The competences of librarians for open science development” conducted by Research Department of SB RAS State Public Scientific and Technological Library among 4th year students of Specialty 51.03.06 “Library Information Activity” in 2024. The obtained results evidence that the students apprehend the communicative component and, to some degree, social orientation of open science. They are also ready for holding educational events and disseminating content revealing the open science principles. However, they have difficulties with civil science efforts, social partnership and valid legal standards in copyright and related rights, as well as with the delivery of communicative components and social orientation of open science. To eliminate the above mentioned problems, based on the survey results, the free short training course has been developed and development of the enhanced program has begun.