Objective <p>Advance care planning (ACP) is a process in which older adults with good cognitive ability communicate about end-of-life care with significant others. This study aimed to explore the intergenerational communication of ACP between older adults and their adult children in Taiwan, including their concerns and experiences at the individual and dyadic levels.</p> Methods <p>This qualitative dyadic study included older adults and their adult children. Individual semi-structured interviews included their experiences and interactions about ACP, and thematic analysis were conducted.</p> Results <p>Nine pairs of older adults and children were recruited. Four themes were identified. First, “good death and peace for both sides” indicated agreement between older adults and their children that the goal of ACP was to achieve a good death without increasing physical suffering for older adults or care burden for children. Second, “the foundation of the ACP discussion” focused on the need to consider ACP knowledge and relevant experiences about illness, care, and death. Third, “mutual understanding without direct discussion” suggested that they may not officially and directly discuss ACP, but older adults express their willingness and children may understand and respect this willingness through progressive and casual communication. Finally, “interpersonal relationships and family dynamics” emphasized the influence of close relationships with older adults and family dynamics between siblings on ACP communication.</p> Conclusion <p>Discussions on ACP occur during casual communication between older adults and their children. This discussion is shaped by ACP knowledge, previous experience with illness and care, trigger events, and family dynamics.</p>