According to the literature, it is assumed that fear and anxiety are basic emotions in anxiety disorders. Many recent studies report that disgust, as well as fear, has an important role in the etiology and maintenance of anxiety disorders. Evaluation of the role of disgust in anxiety disorders has led the theoretical and empirical literature in a new direction, beyond the traditional emphasis on fear. Most of this basic research has focused on specific phobias, such as blood-injection-injury phobia and spider phobia. Findings obtained from evaluation of physiological and cognitive processes, and subjective and behavioral experiences clearly show that in addition to fear, emotional reactions to phobic stimuli also include disgust; however, empirical studies show that disgust and fear have different relative impacts on specific phobias. To illustrate, individuals experience disgust as the basic emotion in blood-injection-injury phobia, whereas both fear and disgust are experienced in spider phobia. Nevertheless, it is concluded that fear has a more fundamental role in the latter. Yet, research indicates that basic emotions different from those identified from neural structures or physiological responses, such as heart rate, can be identified if facial expressions and cognitive appraisals are taken into account. In the present review the role of fear and disgust in blood-injection-injury phobia vs. spider phobia are discussed, based on the relationship between the phobias and disgust sensitivity, disgust as part of phobic responses, and disgust-motivated avoidance behavior.