Socio-cultural and behavioural factors are often not adequately considered in designing health promotion programs for culturally and linguistically diverse communities in Australia. Given that people of Vietnamese background are disproportionately impacted by hepatitis B, the aim of this research was to better understand these factors to inform hepatitis B health promotion messages for the Vietnamese community. Twenty participants (four living with hepatitis B) were interviewed by a Vietnamese-speaking researcher. The interview sessions explored beliefs about health, the body and liver; knowledge and attitudes about hepatitis B vaccines, testing, clinical management and stigma; and sources of health information and value given to information on social media. Participants had a range of understandings of health and hepatitis B which informed their responses to health education and intervention. Participants appeared to have limited knowledge and misconceptions about transmission, prevention, treatment, and management of hepatitis B. Stigma surrounding hepatitis B was apparent, with over half the participants reporting that they distanced themselves from people living with hepatitis B. Participants preferred online information resources for younger people and traditional media in the Vietnamese language for older people. By understanding what Vietnamese people know about hepatitis B and how they access health information, these findings can be used to inform health promotion campaigns using print, media, and radio to ensure wide reach. Knowledge of community specific information is key to reducing the burden of hepatitis B among culturally and linguistically diverse communities and ensuring they are able to access healthcare services for testing, monitoring, and care.