Background: Good mood control has an important effect on adolescents’ control of their blood glucose level. Adolescents with diabetes face major stressors during the course of their disease which can lead to poor adherence to treatment plan and hormonal changes affecting proper glycemic control. Aim: The aim of this study was to examine the effect of mood as a predictor of blood glucose level in adolescents with type 1 diabetes. Materials &Methods: Research design: A descriptive cross- sectional design was utilized to conduct the study. Settings: Pediatrics clinic at Zagazig University Hospitals and the health insurance clinic for diabetes located at director street in Zagazig city. Tools of data collection: The following tools were used by the researcher for data collection, namely a Self-Administered Questionnaire including the following parts: sociodemographic data sheet, Profile of Mood States- Adolescents (POMS-A). Results: The results revealed that there was there was a statistically significant positive correlation between confusion and Random Blood Sugar ( RBS) and between depression and HbA1c. Duration of T1D and depressive mood were the statistically significant independent positive predictors of a score of HbA1c. Conclusion: The current study concluded that depressed and confused mood have a significant effect on blood glucose level among diabetic adolescents. Recommendations: The adolescents with type 1 diabetes should be given health education programs about proper coping with mood disorders throughout their daily activities through teaching relaxation techniques, meditation and proper time management

Keywords : Type 1 Diabetes , Blood Glucose Level; Adolescents; Mood.