Objective: This study aims to investigate the influence of blood glucose control on tuberculosis risk. Methods: A 6-year cohort study was conducted on 60,283 subjects in Nanjing, Jiangsu Province. After excluding active tuberculosis patients identified during baseline screening, subjects were matched with tuberculosis patient management information in Nanjing to identify active tuberculosis cases. Cox proportional hazards models were employed to compare tuberculosis incidence risk between diabetes and non-diabetes patients, adjusting for age, gender, and other factors. Additionally, the incidence of tuberculosis was compared between groups with good and poor blood sugar control. Results: During the 6-year follow-up, 79 cases of active tuberculosis were identified, yielding an incidence density of 25.6 per 100,000 person-years (95% CI: 20.4-31.7). Among these cases, 21.9% (17/79) were diabetes patients, with an incidence density of 58.8 per 100,000 person-years (95% CI: 35.4-92.2). Non-diabetes patients constituted 78.5% (62/79) of cases, with an incidence density of 22.1 per 100,000 person-years (95% CI: 17.1-28.2). The incidence density of active tuberculosis was 227/100,000 person-years (95% CI: 17.7-28.7) in the group with good blood glucose control and 74.3/100,000 person-years (95% CI: 41.3-103.8) in the group with poor blood glucose control. The risk of tuberculosis was 3.766 times higher in the group with poor blood glucose control compared to the group with good blood glucose control (HR=3.766, 95% CI: 2.054-6.906, P<0.001). Conclusion: This large-scale cohort study demonstrates that diabetes patients with poor blood glucose control have an increased risk of tuberculosis. Enhanced screening of diabetes patients with poor blood glucose control may facilitate early detection of tuberculosis, potentially reducing its incidence and prevalence in China.