Based on findings from the adult literature, this study examined the role of negative self-images (NSI) in social phobia during adolescence. NSI was manipulated among 21 nonphobic (IMAG) adolescents (M age = 14.05 years, SD = 1.56) during two social tasks. Self and observer-rated anxiety and performance as well as co-occurring cognition were compared to 21 adolescents with social phobia (SOC) and 21 control adolescents not instructed to use self-imagery. Few differences in observer-rated anxiety or performance were found between the IMAG and control groups, whereas SOC adolescents were consistently rated as more anxious and poorer social performers. Nonsignificantly higher rates of anxiety were reported by the IMAG group compared to controls, but anxiety was not associated with decrements in performance or social skill. A significantly fewer number of on-task thoughts reported by IMAG adolescents suggests that inability to attend to the interaction itself, rather the presence of NSI, served to increase anxiety.