The purpose of this review is to synthesize the evidence and determine the efficacy of interventions based on family systems theory in diabetes-related family conflict, self-management, and glycemic control among adolescents with type 1 diabetes. A systematic search of five English databases was conducted. Interventions based on family systems theory in adolescents with type 1 diabetes that reported diabetes-related family conflict, self-management, and glycemic control as outcome variables were included. A total of 14 articles from ten interventions were included. Meta-analysis results revealed that, compared to adolescents who received usual care, adolescents who received family systems theory interventions reported fewer diabetes-related family conflicts with a medium effect size of 0.32 (p < 0.05), but there was no significant improvement on self-management or glycemic control (p > 0.05). Family systems theory interventions appear to have beneficial effect on reducing diabetes-related family conflicts for adolescents with type 1 diabetes. Adolescents who have type 1 diabetes and their families may need multidimensional psychosocial programs accompanied by diabetes education to improve glycemic control.