Abstract Background: Up to 2.4 million people in the US live with chronic hepatitis B (HBV) infection (Wong et al., 2021). Foreign-born communities are most impacted, particularly those from Asia, the Pacific Islands, the Caribbean, and sub-Saharan Africa (Conners et al., 2023). Individuals with unmanaged HBV have a 15-40% lifetime risk of dying prematurely from cirrhosis or hepatocellular carcinoma (HCC) (McMahon, 2009). Low awareness, cultural norms, and misperceptions about HBV, HCC, and their connection contribute to low screening and care rates in affected communities. A more robust and comprehensive understanding of these barriers is needed to design effective awareness campaigns to improve HBV screening and care and prevent HCC. To this end, this study aimed to learn about existing knowledge and misconceptions about HBV and its relationship to HCC in high-risk communities, identify barriers to screening, and use the findings to develop effective communication strategies that raise awareness and dispel myths. Methods: Fifteen focus groups and two key informant interviews with community members, leaders, and public health experts were conducted to assess beliefs and attitudes about HBV and HCC and to identify preferred communication strategies. Results: The link between HBV and HCC remains poorly understood, and myths persist about the transmission and outcomes of both conditions. Multiple barriers to HBV and HCC screening exist, including concerns about insurance and immigration status, language barriers, cultural and religious beliefs, lack of general health literacy, lack of resources to cope with a positive diagnosis, widespread distrust of Western medicine, and fear of stigma and isolation. Ideas for effective communication methods included employing community health educators, primary care providers, ethnic media outlets and personal testimonials for delivery of information, and tailoring communications by community, age, and gender. These findings were used to create a suite of culturally and linguistically appropriate educational materials for use in each of twelve communities. Conclusions: Many challenges to increasing screening persist in groups most impacted by HBV and HCC, including a need for increased awareness about their connection. Community engagement is essential to overcoming these challenges, as are specific, targeted messaging and dissemination to improve the uptake of HBV screening and management. Behavioral and Social Science: Community-based Participatory Research Citation Format: Beatrice Zovich, Fiona Borondy-Jenkins, Suzanne Block, Kate Moraras, Thomas Chen, Chari Cohen. Qualitative assessment of knowledge gaps and barriers to Hepatitis B and liver cancer screening in high-risk U.S. communities [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr B074.