Despite extensive evidence relating attachment dimensions to maladaptive interpersonal behaviours and dysfunctional emotion regulation strategies, few studies have explored social anxiety in the context of adult attachment dimensions. The aim of the present study was to investigate whether attachment-related anxiety and avoidance are associated with symptoms of social anxiety and whether cognitive emotion regulation strategies (reappraisal and suppression) play a role in the relationship between adult attachment and social anxiety. A sample of 253 adults (male n = 47, 18.6%; female n = 202, 79.8%; gender not disclosed n = 4, 1.6%) ranging in age from 18 to 74 years (M = 33.12, SD = 11.56) completed an online questionnaire that consisted of the Experience in Close Relationships-Revised Questionnaire (ECR-R); The Inventory of Interpersonal Situations Discomfort scale (IIS-D); and The Emotion Regulation Questionnaire (ERQ). Results indicated that both attachment anxiety and attachment avoidance have a direct effect on indices of social anxiety symptomology. Reappraisal partially mediated the relationship between attachment anxiety and social anxiety. However, the relationship between attachment avoidance and social anxiety was not mediated by the use of reappraisal and suppression. Findings of the study have implications for the development of clinical interventions targeting mediators of psychological distress associated with social anxiety.