Objective: The quantitative measurement and antecedents of doctoral well-being have not been sufficiently explored in the extant literature, creating a significant gap based on alarming statistics of high attrition rates and psychological distress among PhD scholars. Therefore, based on the theory of conservation of resources, our study examines the role of personal resources such as harmonious passion (HP), Grit, and psychological capital (PsyCap) in enhancing PhD students' well-being. Additionally, it proposes a novel conceptualisation of doctoral well-being, combining research engagement (eudaimonic well-being) and satisfaction (hedonic well-being). Method: We use structural equation modelling to analyse data collected from 239 doctoral students in India's higher educational institutions (HEI). Results: The results show that HP and Grit are significantly and positively associated with doctoral students' well-being while PsyCap partially mediates the relationship of HP and Grit with well-being. Conclusions: HP and Grit are personal resources which can enhance doctoral students' well-being. PsyCap assists in this process through resource gain whereby students with higher personal resources could gather further resources, leading to hedonic and eudaimonic well-being. The study also highlights practical implications for supervisors and management of HEIs.