COVID-19 vaccine hesitancy among nurses is a global public health concern and it is imperative to understand associated factors. Information environment plays a critical role in shaping health behaviors, while few studies explored such effects in the context of COVID-19 vaccination. A cross-sectional survey was conducted among 1902 nurses in China. The study investigated the effects of social media exposure/interpersonal discussion on intention of COVID-19 vaccination and tested whether perceived effectiveness of COVID-19 vaccines (perceived vaccine efficacy, perceived duration of protection, and perceived effectiveness in preventing resurgences) mediated such associations. Results showed that about 68.0% and 56.5% of the participants had an intention of free and self-paid COVID-19 vaccinations, respectively. Frequent social media exposure and interpersonal discussion were positively associated with vaccination intentions. Perceived vaccine efficacy significantly mediated the effects of frequent social media exposure and interpersonal discussion, whereas perceived effectiveness in preventing resurgences suppressed the effects of frequent social media exposure. In conclusion, the prevalence of intention of COVID-19 vaccination was relatively low among Chinese nurses and health promotion is needed. Frequent social media exposure and interpersonal discussion potentially enhanced vaccination intentions via increased perceived vaccine efficacy. The findings can help inform the development of relevant health communication interventions.