CONTEXT: Type 1 diabetes mellitus (T1DM) is a chronic disease, mainly observed in children or youth, with a significantly increased incidence in young children. Structured therapeutic patient education (TPE) is a must to help them manage their disease effectively and lead a healthy lifestyle. AIMS: This study aimed to assess the effects of a structured TPE program on glycemic markers and quality of life (QOL) of T1DM children and adolescents in Fez city, Morocco. SETTINGS AND DESIGN: It is a quasi-experimental study. MATERIALS AND METHODS: One hundred T1DM children and adolescents, aged 8-18, participated in a TPE intervention at the pediatric department in a hospital center in Fez, Morocco. Glycemic markers were measured and QOL was assessed by a validated questionnaire. STATISTICAL ANALYSIS USED: Parametric and nonparametric tests were used and statistical significance determined by < 0.05. RESULTS: At 3 months' follow-up, both global and dimensional QOL mean scores improved significantly ( ≤ 0.0001), whereas glycosylated hemoglobin (HbA1c) decreased (10.28% vs. 10.62%), tough with no statistical significance ( = 0.160). Furthermore, a significant improvement was observed in the maximum preprandial (2, 11 g/L [1.51-2.58] vs. 2, 37 g/L [1.81-3.21], = 0.001) and postprandial blood glucose levels (2, 50 g/L [1.90-3.27] vs. 2, 95 g/L [2.07-3.99], = 0.001) after 3 months; with no significant change in their minimum. CONCLUSION: Although this TPE intervention was more effective in improving patients' QOL than their HbA1c, it is worth striving to implement regular TPE programs for T1DM pediatric patients and adjust them to achieve a better patients' glycemic markers levels.