Research has supported a link between insecure attachment and eating disorders (EDs) in adolescents; however, mechanisms accounting for this association remain unclear. Growing evidence suggests impaired mentalizing as a potential mechanism. Yet, little is known about the relationship between mentalizing and ED symptoms or how it relates to the link between attachment and EDs in adolescents. This study examined mentalizing deficits in adolescents with ED symptoms relative to psychiatric and healthy controls and tested a mediational model, wherein mentalizing capacity mediates the relationship between attachment and ED symptoms.