Aristotle (4th century B.C.E/1925) described eudaimonia as “the good life”, and is today commonly understood as eudaimonic well-being (EWB) within research. Despite the long history, the definitions and operationalizations of EWB are diverse and no coherent description or explanation for the biology of EWB exist. Hence, the present thesis reviews current neuroscientific- and additional biological research on EWB. This review reveals EWB to be most frequently operationalized as psychological well-being (PWB) (Ryff, 2014), and is here used as basis for an attempt to explain the biological and psychological profiles of EWB as high PWB. High PWB was characterized by brain activity linked to the reward circuitry, dorsolateral and left prefrontal cortex (PFC) and grey matter (GM) volume in areas of the brainstem and insular cortex. High PWB was also positively related to lower levels of several harmful biomarkers. The proposed psychological profile of high PWB included the psychological functions goal directed behaviour and emotional control. It is hoped that the proposed profiles will serve as inspiration for further exploration of the biology and psychology of human well-being (WB).