Background: In certain places, tuberculosis (TB) and diabetes mellitus (DM) are strongly linked as frequent comorbidities and might be termed epidemics combined. Objective: The present work aimed to detect relationship between type 1 DM (T1DM) and latent TB. Patients and Methods: This comparative cross-sectional study was conducted over the period from October 2019 to October 2020. It included 81 cases had type 1 DM and 81 healthy children as control group. This study was conducted at Zagazig University Pediatric Hospital.  All patients were subjected to the following: Full history taking, full general examination, and investigation (Tuberculin test and chest X ray). Results: In the current study, 42% were male and (58%) were female. In the present work, there was no statistically significant difference between cases group and controls group regarding anthropometric measurements. This study showed that, the percentage of positive tuberculin test was higher among cases group than controls group (32.1%, 7.4%) p value< 0.001. OR estimate for DM on risk of TB was 5.9 (95% CI 2.27 to 15.33). Conclusion:      There was no statistically significant difference between diabetic group and control group regarding sex, age, weight, and height. There was no statistically significant difference between diabetic and control group regarding contact with patient with TB and passive smoking. The percentage of positive tuberculin test was higher among diabetic group than control group.