Anorexia nervosa (AN) could be considered a form of obsessive-compulsive disorder in which an impairment of the cognitive domain related to decision-making was found. We explored this function in AN patients, as well as possible differences between restricting type and binge/purge type, with the aim of examining the hypothesis that AN is part of the obsessive-compulsive spectrum. Decision-making was assessed in 59 inpatients with AN and 82 control subjects using the Gambling task, which simulates real-life decision-making by assessing the ability to balance immediate rewards against long-term negative consequences. We confirmed the supposed deficit of decision-making in AN. However, restricting and binge eating/purge subtypes showed different patterns of decision-making impairment. Poor performance on the Gambling task is not a mere consequence of starvation and does not appear to be related to illness severity. The decision-making deficiency that some AN patients show is linked to those individual features that contribute to the phenomenological expression of the disorder.