Abstract: Medical libraries can utilize their advantages in resources, technology and manpower to carry out livestreamed health science popularization activities, thereby fulfilling their social and educational functions. This study takes a series of health science popularization livestreaming activities undertaken by Fudan University Medical Library as a case study. Drawing on activity theory, it analyzes the activity elements and interactive behaviors involved in health science popularization live streaming. Using the narrative framework of “science popularization motivationlive streaming deployment and implementationscience popularization outcome”, the activities are systematically examined through six elements: subject, object, tool, community, rules and division of labor. Based on their interactions, the interrelated systems are establised: content production system, narrative sharing system, behavioral norms system, and external collaboration system. Together, these systems outline the action pathway for medical libraries to participate in livestreamed health science popularization. This study provides a reference for libraries and other professional organizations to launch sustainable science popularization activities through live streaming. It further suggests that effective health science popularization practices can be advanced by embracing new health communication technologies, activating scientists science popularization potential, and collaborating with multiple actors to cocreate valuedriven science popularization networks.

Key words: Medical libraries, Health science popularization, Live streaming, Activity theory