Although greater parent-child attachment security is linked with children's lower levels of depressive symptoms, little research has evaluated potential explanatory mechanisms. We investigated whether dispositional gratitude and interpersonal forgiveness explain the relation between attachment security with parents and early adolescents' depressive symptoms. Early adolescents (N = 105; M age = 12.3 years; 51% girls) completed questionnaires assessing their attachment security to mother and father figures, depressive symptoms, and dispositional gratitude, and an interview assessing interpersonal forgiveness. Results revealed that greater attachment security to mothers and fathers was associated with fewer depressive symptoms and greater levels of dispositional gratitude and interpersonal forgiveness. Further, dispositional gratitude and interpersonal forgiveness were negatively associated with depressive symptoms. Dispositional gratitude emerged as a mediator between attachment security with each parent and depressive symptoms. Our findings suggest that greater parent-child security may promote early adolescents' appreciation of positive events, which in turn may relate to fewer depressive symptoms.