The Attachment Pictures Story (APS) is an adaptation of the Patte Noire thematic projective test to evaluate internal representations of attachment in adolescents. It consists in analyzing the responses to the stories in seven selected pictures, which elicit attachment experiences. The purpose of this study is to describe the development and verification of the reliability and validity parameters of the APS based on a sample of 77 adolescents between the ages of 12 and 18 years (M = 14.71; SD = 2.07) who were enrolled in schools in Spain. The results show evidence of the instrument s psychometric properties. Satisfactory content validity through inter-rater agreement of four experts for pictures and items as well as suitable reliability indexes were found. The exploratory factory analysis confirms the five preestablished categories based on theory (secure/insecure avoidant, insecure fearful, insecure resistant, and unresolved). The APS appears to be a psychometrically suitable instrument for evaluating attachment patterns in adolescents in a quantitative and qualitative way. Having a specific projective test that helps us understand adolescents may be useful in facilitating the expression of early and sometimes adverse attachment relationships, which are difficult to externalize.