Objectives: Stigmatising attitudes towards mental illness are an established barrier to help-seeking in adolescent males with anxiety. This study aimed to investigate specific forms of personal mental health stigma elicited in response to vignettes of individuals with clinical and non-clinical symptoms of anxiety within a sample of Australian adolescent males. The relationship between stigma and mental health help seeking was also investigated. Methods: Seven hundred and two males (aged 12–18 years) completed a vignette-based mental health literacy survey and measures of help-seeking attitudes, intentions and behaviour online. Open-response items were coded for frequency, intensity and form of stigma. Results: A larger percentage of participants exhibited stigma in response to the non-clinical vignette than in response to the non-clinical vignettes. Stigmatising comments towards the non-clinical vignette were also found to be more severe than towards the clinical vignettes. When stigma occured, it was predominantly related to a belief that a mental disorder was due to a personal weakness. Individuals who used stigmatising comments were also more likely to have negative views towards help-seeking. Yet individuals who made stigmatising comments about a peer with clinical social anxiety were more likely to have previously sought mental health help. Conclusions: It is uncommon for adolescent males to hold stigmatising views towards other adolescent males with clinical levels of anxiety. More severe stigma is evident in response to experiences of normative levels of anxiety in response to an event which would typically be considered mildly anxiety-provoking (leaving home to go to university). Implications for youth mental health initiatives targeting help-seeking for anxiety in adolescent males are discussed.