Recently, death anxiety, or dread of death, has been proposed as a key transdiagnostic process underlying the anxiety disorders, depressive disorders, somatic disorders, and trauma and stressor-related disorders. In fact, it has been argued that death anxiety underlies all psychopathology, and is more fundamental than perfectionism, a process which was previously considered the root of mental illness. However, there has been a paucity of research examining the relationship between death anxiety and the eating disorders, although these conditions have been found to be strongly related to perfectionism. The present study therefore aimed to examine whether death anxiety is related to disordered eating, and whether death anxiety is a better predictor of disordered eating than perfectionism. A sample of 164 participants (132 female), average age 33.55 years (SD = 15.45 years), completed an online survey comprising background questions (age, sex, diagnosed psychiatric disorder), the Eating Attitudes Test - 26 item version (EAT-26), the Almost Perfect Scale - Revised (APS-R), the Rosenberg Self-Esteem Scale (RSES), and the Death Anxiety Scale (DAS). The findings of a hierarchical multiple regression analysis with EAT-26 as the dependent variable, age entered at Step 1, the RSES and APS-R entered at Step 2, and the DAS entered at Step 3 showed that only death anxiety and self-esteem were independent predictors of disordered eating at Step 3. A simultaneous multiple regression analysis was subsequently run with age and the APS-R alone as predictors of EAT-26 scores. This analysis showed that perfectionism was only a predictor of disordered eating when death anxiety and self-esteem were not included in the regression model. Death anxiety and self-esteem both appear to be important transdiagnostic processes.