The Clark and Wells (1995) model of social phobia proposes that there are three types of maladaptive self-beliefs responsible for persistent social anxiety (high standard, conditional, and unconditional beliefs). Another prominent feature of social phobia is the avoidance of social-evaluative situations. To our knowledge, there have been no studies that have examined the relationship between these specific maladaptive self-belief types and avoidance. We hypothesised that while accounting for potential confounding variables (i.e., fear of negative evaluation and general symptomology), each of the three maladaptive self-belief types would be significantly and positively associated with cognitive and behavioural avoidance in the social domain, but not these forms of avoidance in the non-social domain. In a sample of undergraduates (N = 361), we found only partial support for our hypotheses. In the social domain, stronger high standard beliefs predicted less behavioural avoidance, stronger unconditional beliefs predicted more behavioural avoidance, and stronger conditional beliefs predicted more cognitive avoidance. In the non-social domain, stronger unconditional beliefs predicted more cognitive avoidance. These relationships were obtained at all levels of social anxiety. Additionally, the unconditional beliefs partially mediated the relationship between social anxiety and behavioural avoidance in the social domain, and the conditional beliefs fully mediated the relationship between social anxiety and cognitive avoidance in the social domain. These results emphasise the distinct nature of each of the maladaptive self-belief types and the need to elucidate their relationship with other components in theoretical models of social phobia.