ObjectiveWe assessed the associations of family wellbeing with verifying and subsequently forwarding COVID-19-related information to family members and the mediating effect of the quality of family communication on these associations among Chinese adults in Hong Kong.MethodsUnder the Jockey Club SMART Family-Link Project, we conducted an online population-based survey, using Family wellbeing Scale and questions related to the family communication quality and forwarding and verifying COVID-19 information. Data were collected from 4,891 adults in May 2020. Prevalence estimates of forwarding and verifying COVID-19 information were weighted by sex, age, and education of the general population, and their associations with family wellbeing (ranged 0–10) were analyzed using generalized linear models with mutual adjustment. Their interactive effects on family wellbeing and the mediating effects of family communication quality were examined.ResultsIn total, 53.9% of respondents usually/always forwarded COVID-19 information related to their family, 68.7% usually/always verified it before forwarding, and 40.9% did both. Greater family wellbeing was associated with usually/always forwarding [adjusted β (95% CI): 0.82 (0.72–0.92)] and usually/always verifying [0.43 (0.32–0.55)] (both P < 0.001) the information. Forwarding and verifying such information showed an additive effect on family wellbeing [1.25 (1.11–1.40)]. Family communication quality mediated the associations of family wellbeing with forwarding (83.7%) and verifying (86.6%) COVID-19-related information.ConclusionForwarding COVID-19 information to family, verifying such information, and especially doing both, were associated with greater family wellbeing, being strongly mediated by the quality of family communication. Individuals should be encouraged to verify COVID-19-related information before forwarding it to family members amidst the COVID-19 pandemic.