Background: With the spread of the coronavirus disease 2019 (COVID-19), strict laws such as quarantine were implemented in many countries, including Iran. The spread of this disease and the general quarantine overshadowed the treatment and management of some chronic diseases, including type 1 diabetes, and many families faced a serious challenge in providing medicines and periodic tests for their children. This study was conducted with the aim of investigating the effects of the COVID-19 crisis on disease management in children with type 1 diabetes. Method: Based on a researcher-made questionnaire, this cross-sectional study was conducted on 85 children with type 1 diabetes between the ages of 2 and 18 years in 6 months at the Children's Medical Center Hospital. This questionnaire is either collected from the parents during the face-to-face visit of the child with type 1 diabetes, or the virtual visit (telemedicine), and they were asked to complete the relevant questionnaire. This questionnaire included demographic information, laboratory tests, and the challenges of patients' families during the pandemic. In order to properly understand the management of this disease, parents were asked to enter the results of tests related to fasting blood sugar and HbA1c 3 times at the beginning of the pandemic, during quarantine, and during the implementation of the study. Results: Based on the results, the level of HbA1c, the problem of insurance coverage, the problem of attendance, ketoacidosis, and infection before the pandemic, during the pandemic, and at the time of the study among children with type 1 diabetes were unchanged (P>0. 05). There was a significant difference between fasting blood sugar levels, insulin levels, blood sugar control levels, and hospitalizations in type 1 diabetes patients before the pandemic, during the pandemic, and the study period (P<0. 05). Conclusion: Increasing the use of continuous glucose monitors and the widespread use of telemedicine visits may improve the impact of the pandemic on disease management. It is suggested that more multicenter studies with a higher sample size should be conducted in order to investigate the impact of the COVID-19 crisis on children with diabetes.