This study examined potential subgroups of patients with generalized social anxiety disorder (SAD) based on novelty-seeking tendencies. Eighty-two outpatients with DSM-IV generalized SAD were recruited from an outpatient anxiety clinic and assessed with the Tridimensional Personality Questionnaire. The novelty-seeking subscales, reflecting risk-prone and disinhibited behavior tendencies, served as dependent measures in a series of cluster analysis procedures. Two qualitatively different SAD subgroups were identified: (1) low novelty-seeking tendencies and (2) high-novelty-seeking tendencies. These groups did not differ in social anxiety symptom severity. Women were less likely to be classified in the high-novelty-seeking group. Clinician severity ratings for comorbid substance use disorders were greater in the high-novelty-seeking group. These findings contribute to growing evidence for the heterogeneity of SAD. High-novelty-seeking, risk-prone, and disinhibited behavior tendencies are a characteristic feature of a distinct subgroup.