OBJECTIVES: To epidemiologically assess the influence of COVID-19 pandemic on newly diagnosed type 1 diabetes mellitus presenting with diabetic ketoacidosis at the teaching hospital of the university, Eastern province, Saudi Arabia. METHODS: We enrolled newly diagnosed type 1 diabetes mellitus cases among pediatric patients attending the emergency department and outpatient clinics during 2019-2021. The participants’ data were collected from electronic medical records which included patients’ age at diagnosis, sex, nationality, height, weight, year of diagnosis, length of stay, presentation, random blood sugar, blood gas readings, electrolyte panel, and time of resolution of the diabetic ketoacidosis if present. RESULTS: 108 patients were included with an average age of 8.87 ± 4.21 years and 53.70% were females. The demographic characteristics of all diabetic pediatric patients prior to COVID-19 and during COVID-19 were studied and the difference was statistically insignificant. Furthermore, initial pH and HCO3 tests were found to be lower in the moderate to severe diabetic ketoacidosis group (7.17 and 11.2, respectively) compared to the mild group (7.27 and 15.50, respectively) and the differences were statically significant (P < 0.001). CONCLUSION: Patients newly diagnosed with type 1 diabetes mellitus during the COVID-19 pandemic tended to have a more severe presentation of diabetic ketoacidosis in terms of PH and HCO3.