Background and Aims: Diabetes has been reported to be a risk factor for sleep disturbances in adolescent age groups. Although the impact of type1 diabetes mellitus (T1DM) on sleep patterns of children is well recognized, data about its prevalence is scant. This study aims to determine the quality of sleep among adolescents with T1DM and factors inuencing it. Methods: This is a cross-sectional study collected data from 30 adolescent diagnosed with T1DM at least 6 months earlier. They presented to Paediatric endocrine OPD from May 2021 to May 2022. Subjects were asked to complete the Pittsburgh Sleep Quality Index (PSQI) 19-item self-report questionnaire. Children with T1DM being under treatment for sleep disorder were excluded. The combined score of the 7 components (subjective sleep quality, sleep latency, sleep duration, habitual sleep efciency, sleep disturbances, use of sleeping medication, and daytime dysfunction) was used for analysis and the score ranged from 0 to 21. Atotal score >5 was considered as “poor sleep quality”. The quality of sleep was correlated with drug, dietary compliance and metabolic control. p-value <0.05 was considered signicant. Results: The mean age of study population was 14.3±1.7 years. 18 were boys and 12 were girls. Total 8 patients showed poor sleep quality (PQSI score >5). No signicant relationship was found between sleep quality, duration of diabetes and HbA1c levels in the diabetes group (P= 0.59, P= 0.41, respectively). The total sleep time of boys (8.4 ± 1.2 h) was longer than girls (7.6 ± 1.7 h), but the overall total sleep time per night did not differ signicantly between boys and girls (P= 0.053). Conclusion: The present study shows that diabetes control may affect sleep quality in adolescents. Optimal diabetes management can positively affect sleep patterns in these adolescents. Further larger studies are needed to validate our results