Objectives. To analyze the relationship between attachment and self-esteem in young people and adolescents, and to examine the relationship between self-esteem and social self-expression skills, integrating these results into a causal chain model. Method. 387 adolescents and young people completed self-report scales. Regression analysis and structural equation modeling were performed. Results. Both secure and insecure attachment predicted participants’ self-esteem. Likewise, self-esteem was a predictor of social self-expression. The study concluded that the secure attachment established with the caregivers increases the possibility of developing a strengthened self-esteem, promoting the individual’s ability to express oneself socially. Conversely, insecure attachment weakens self-esteem, leading to impaired social self-expression.Objetivos. Analizar la relación entre el apego y la autoestima en jóvenes y adolescentes y examinar la relación entre la autoestima y la autoexpresión social, con el fin de integrar los resultados en un modelo de encadenamiento causal. Método. Participaron 387 adolescentes y jóvenes quienes completaron autoinformes. Se realizaron análisis de regresión y modelado de ecuaciones estructurales. Resultados. Tanto el apego seguro como el inseguro predijeron significativamente la autoestima de los participantes. La autoestima resultó ser un predictor significativo de la autoexpresión social. Se concluye que el apego seguro aumenta la posibilidad de desarrollar una autoestima fortalecida y esta, a su vez, promueve la capacidad del individuo para expresarse socialmente. Contrariamente, el apego inseguro debilita la autoestima, lo que conduce a un detrimento de la autoexpresión social.Objectives. To analyze the relationship between attachment and self-esteem in young people and adolescents, and to examine the relationship between self-esteem and social self-expression skills, integrating these results into a causal chain model. Method. 387 adolescents and young people completed self-report scales. Regression analysis and structural equation modeling were performed. Results. Both secure and insecure attachment predicted participants’ self-esteem. Likewise, self-esteem was a predictor of social self-expression. The study concluded that the secure attachment established with the caregivers increases the possibility of developing a strengthened self-esteem, promoting the individual’s ability to express oneself socially. Conversely, insecure attachment weakens self-esteem, leading to impaired social self-expression.