Background:Sleep quality plays a vital role in maintaining optimal glycemic control in patients with Type 2 Diabetes Mellitus (T2DM). Emerging evidence suggests that sleep disturbances may contribute to insulin resistance and poor metabolic outcomes. However, in many populations, the association between sleep quality and glycemic control remains underexplored.Materials and Methods:This cross-sectional study was conducted among 200 adult patients with T2DM attending the endocrinology outpatient department of a tertiary care hospital. Participants were assessed for sleep quality using the Pittsburgh Sleep Quality Index (PSQI), with a global score >5 indicating poor sleep quality. Glycemic control was evaluated using the most recent HbA1c levels, with a cutoff of 7% to distinguish between controlled and uncontrolled diabetes. Demographic, clinical, and lifestyle data were collected through structured interviews. Results:Among the 200 participants, 124 (62%) had poor sleep quality (PSQI >5), while 76 (38%) reported good sleep quality. The mean HbA1c level was 8.2 ± 1.3% among poor sleepers and 6.9 ± 1.1% among good sleepers. A statistically significant association was observed between poor sleep quality and poor glycemic control (p = 0.001). Logistic regression analysis indicated that poor sleep quality was independently associated with uncontrolled HbA1c (OR: 2.34; 95% CI: 1.30–4.22).Conclusion:Poor sleep quality is significantly associated with suboptimal glycemic control in patients with T2DM. Screening for sleep disturbances and incorporating sleep hygiene interventions into diabetes management strategies may help improve glycemic outcomes.