Because no studies of psychotherapy treatments for night eating syndrome (NES) have been published, we conducted a pilot study of a 10-session cognitive behavior therapy (CBT) for NES. Twenty-five patients (19 female, 6 male) were screened and comprehensively assessed before being enrolled. At each visit, patients completed the Night Eating Symptom Scale (NESS), were weighed, and number of awakenings and the number of nocturnal ingestions and daily caloric intake were calculated from weekly food and sleep records. Mixed model regression analyses [of the data] showed significant decreases in caloric intake after dinner (35.0% to 24.9%); number of nocturnal ingestions (8.7 to 2.6 per week); weight (82.5 to 79.4 kg); and NESS score (28.7 to 16.3; all p values <0.0001). Number of awakenings per week, depressed mood, and quality of life also improved significantly (p values <.02). This first clinical trial of CBT for NES shows significant improvements in the core aspects of NES and weight reduction, suggesting the need for a controlled treatment trial.