Objective An unusually high comorbidity of eating disorders and alcohol abuse has been found in clinical and community samples of young women. This paper proposes that individual differences in sensitivity to reward and punishment may influence the propensity of young women to engage in dysfunctional eating and drinking behaviour. Method The Drive for Thinness scale, the Alcohol Use Disorders Identification Test and the BIS/BAS scales were administered to 232 high school girls. Results Heightened sensitivity to reward was the better predictor of alcohol misuse while heightened sensitivity to both reward and punishment was predictive of dysfunctional eating. When categorised by group, alcohol abusing, dysfunctional eating, and comorbid girls reported greater sensitivity to reward than non-disordered girls. Girls with dysfunctional eating with and without comorbid alcohol abuse reported greater sensitivity to punishment than alcohol abusing only girls. Discussion These findings suggest that girls who abuse alcohol and have dysfunctional eating may share a vulnerability to heightened sensitivity to reward, yet be differentiated by sensitivity to punishment.