Based on the attachment theory of John Bowlby and Mary Ainsworth, this study explores the substantial impact of attachment types on adolescent peer relationships. Attachment types (secure, anxious, and avoidant) play a key role in shaping relationship dynamics from infancy through adolescence. This in-depth study of the complex interrelationships between attachment styles and adolescent peer interactions provides important insights into understanding the development of social relationships during this critical life stage. During adolescence, attachment objects gradually change from primary caregivers to companions and romantic objects. Secure attachment is closely related to adolescents’ resilience, emotional regulation, and self-esteem levels, enabling them to confidently handle peer relationships. In contrast, individuals with anxious or avoidant attachment types face many challenges in establishing and maintaining positive peer interactions. Secure attachment lays the foundation for trust, emotional resilience, and positive peer interaction, while insecure attachment creates complexity and challenges. This effect also extends to the areas of self-esteem and mental health in adolescents, with secure attachment being associated with a reduced incidence of anxiety and depression. Future research should explore cross-cultural differences in attachment types and develop interventions to promote secure attachment in adolescents. This study provides a theoretical basis for cultivating healthy and positive peer relationships, contributes to the overall development of adolescents, reveals the complex and dynamic relationship between attachment styles and adolescent peer relationships, and emphasizes the profound impact of attachment theory on adolescent mental health and its key role in shaping human development.