The present study explored the prevalence of anxiety disorders among adults seeking speech therapy for stuttering. Employing a matched case-control design, participants included 92 adults seeking treatment for stuttering, and 920 age- and gender-matched controls from the Australian National Survey of Mental Health and Well-being. A conditional logistic regression model was used to estimate odds ratios for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) and International Classification of Diseases (ICD-10) anxiety disorders. Compared with matched controls, the stuttering group had six- to seven-fold increased odds of meeting a 12-month diagnosis of any DSM-IV or ICD-10 anxiety disorder. In terms of 12-month prevalence, they also had 16- to 34-fold increased odds of meeting criteria for DSM-IV or ICD-10 social phobia, four-fold increased odds of meeting criteria for DSM-IV generalized anxiety disorder, and six-fold increased odds of meeting criteria for ICD-10 panic disorder. Overall, stuttering appears to be associated with a dramatically heightened risk of a range of anxiety disorders.