The COVID-19 pandemic has had a profound impact on the mental health, adjustment, and psychological well-being of young adults. Despite extensive research conducted in this area, eudaimonic well-being, one specific form of psychological well-being focusing on self-knowledge and self-realization within existential challenges, has received comparatively less attention. The current study aimed to investigate the potential linkages between two key psychological factors, psychological inflexibility and fear of death, with eudaimonic well-being among young adults in the context of the Covid-19 pandemic. One year after the outbreak, 317 young Italian adults (18-34 yrs.) participated in an online survey, including measures of psychological inflexibility (AAQ-II), fear of death (CL-FODS), and eudaimonic well-being (PWB). Results showed that psychological inflexibility was negatively associated with all the dimensions of Ryff’s model of eudaimonic well-being, while fear of death of others was found to be associated with three of these dimensions (autonomy, environmental mastery, and self-acceptance). Results also indicated a mediation role of psychological inflexibility in the association between fear of death and eudaimonic well-being. These findings expand our knowledge of the potential factors that may influence eudaimonic well-being and provide insights for clinical work with young adults challenged by uncertain times.