Despite recent modifications to the DSM-V diagnostic criteria for eating disorders (ED; APA, 2013), sources of variability in the clinical presentation of ED patients remain poorly understood. Consistent with previous research that has used underlying personality dimensions to identify distinct subgroups of ED patients, the present study examined (1) whether we could identify clinically meaningful subgroups of patients based on temperamental factors including behavioral inhibition (BIS), behavioral activation (BAS) and effortful control (EC), and (2) whether the identified subgroups would also differ with respect to ED, Axis-I and Axis-II psychopathology. One hundred and forty five ED inpatients participated in this study. Results of a k-means analysis identified three distinct groups of patients: an Overcontrolled/Inhibited group (n = 53), an Undercontrolled/Dysregulated group (n = 58) and a Resilient group (n = 34). Further, group comparisons revealed that patients in the Undercontrolled/Dysregulated group demonstrated more severe symptoms of bulimia, hostility and Cluster B Personality Disorders compared to the other groups, while patients in the Resilient group demonstrated the least severe psychopathology. These findings have important implications for understanding how individual differences in personality may impact patterns of ED symptoms and co-occurring psychopathology in patients with ED.