With the proliferation of social networks and the development of digital technology, the content structure and propagation mode of rumors have become more complicated with ambiguity, which has greatly influenced people’s behaviors when facing digitalized rumors. Based on the digital storytelling theory, this study takes an early initiative by deconstructing and identifying the basic components of online rumors and revealing the conditions under which people’s sharing behaviors in a social environment. A data set of health-related rumors related to Covid-19 was used to test the research hypotheses. The results indicated that causality explicitness, element integrality and source explicitness have different influences on rumor sharing behavior. And rumor vividness plays a negative moderating effect during the sharing process. This research offers insight to viewers and website authorities on ways to monitor and debunk online rumors.