<p>A long-standing debate has persisted on whether reciprocity reasonably justifies the priority rules in organ allocation as some countries (e.g., Israel, Singapore, Chile, and China) have adopted this priority policy based on reciprocity. This paper reviews the ethical dilemmas and challenges of incorporating reciprocity into a priority system by considering the following five aspects: (1) It exacerbates the risk of incorporating moral values in the organ allocation context. (2) It is incompatible with the reciprocity inherent in the gift- or gratitude-based relationship in organ allocation. (3) The concept of “reciprocity,” which easily extends the idea of “moral desert,” could, thus, exacerbate social inequalities. (4) In the context of incentives instead of rewards, priority rules in organ allocation need not involve the obligation of reciprocity. (5) Reciprocity acceptability does not invariably translate into efficacy. In sum, reciprocity is not an appropriate moral rationale for being established as a priority rule in organ allocation, and alternatives such as altruism or charity (virtue)—though associated with several feasibility and fairness-related concerns—seem preferable.</p>