OBJECTIVE: Etiological models of eating disorders (EDs) suggest there is considerable overlap between anxiety and EDs. In particular, shared clinical features across these psychiatric diagnoses suggest that common threat processes (i.e., changes in affect, cognition, and physiology, or behavior in response to a feared stimulus) underlie their maintenance. Compared to anxiety disorders, however, less is known about the neurobiological bases of threat that may give rise to and maintain ED symptoms, particularly among adolescents. Addressing this knowledge gap will aid in informing future research and interventional efforts. METHODS: We searched four online databases to review studies published through March 2025 comprising all potential types of assessment of biobehavioral activity associated with threat (e.g., neuroimaging, skin conductance) in clinical samples of adolescents with EDs. RESULTS: From 2546 articles identified, N = 19 studies met inclusion criteria. A majority of investigations employed functional neuroimaging to study adolescent girls with anorexia nervosa, compared with age-matched controls. We classified and synthesized evidence within categories of non-ED-specific threat (harm avoidance) or ED-specific threat (bodily- or food-related threat, or their combination). Most studies demonstrated altered ED-specific threat processing in adolescent girls with anorexia nervosa compared to controls, as well as associations between neural threat response and ED symptomology. The study focused on non-ED-specific threat found no noted differences in threat response in cases versus controls. DISCUSSION: Given the apparent relevance of threat processing in EDs, future inquiry is needed to resolve remaining questions and yield new insights with clinical relevance across transdiagnostic adolescent ED presentations.