<p>Aetiological beliefs in the context of social anxiety are beliefs about what has caused one’s social anxiety. These beliefs can potentially influence social anxiety and its treatment, yet it is unclear how individuals with social anxiety might differ in aetiological beliefs and whether any differences in beliefs can be further characterised in terms of clinical and cognitive-behavioural maintaining process outcomes. The current study (not pre-registered) aimed to address these knowledge gaps. An adult community sample with moderate to severe social anxiety (N = 406) completed measures of aetiological beliefs and outcome variables (social anxiety, life interference from social anxiety, depression, maintaining processes). Latent profile analysis divided participants into subgroups (i.e., profiles) based on their aetiological beliefs, and profiles were compared on outcomes. Four profiles emerged and labelled according to perceived causal factors emphasised: Low Diffuse Factors profile (not emphasising any particular factor), High Diffuse Factors profile (emphasising many factors), Parenting Factor profile (emphasising parenting), and Dispositional and Bad Social Experiences Factors profile (emphasising individual tendencies and negative social experiences). The High Diffuse Factors profile had the worst outcomes, followed by the Dispositional and Bad Social Experiences Factors profile, the Parenting Factor profile, and the Low Diffuse Factors profile. Individuals with social anxiety can be differentiated by their aetiological beliefs profile, and profiles differ in clinical and maintaining process outcomes. These findings highlight the clinical relevance of assessing and addressing aetiological beliefs in the treatment of social anxiety.</p>