Onset of anorexia nervosa prior to menarche is rarely encountered and little is known about clinical and psychological differences between this group and the more typical postmenarcheal patient. This cross-sectional investigation compared 26 premenarcheal patients with 69 with secondary amenorrhea. Menarcheal status was confirmed with Tanner scaling obtained via pediatric examination. Duration of illness was equal among the groups. Differences between the groups included higher internal locus of control and need for approval through socially desirable behavior among premenarcheal patients. In addition, premenarcheal patients scored significantly lower on several subscales of the Eating Disorders Inventory. These findings suggest that some of the features associated with anorexia nervosa, including reward dependence, pseudomaturity, and ego-syntonicity (i.e. apparent absence of distress despite the seriousness of the symptoms) are amplified in premenarcheal patients. Methodological problems and clinical implications are discussed.