Euglycemic diabetic ketoacidosis (DKA) is a rare complication of diabetes mellitus (DM) characterized by metabolic acidosis, ketosis, and blood glucose levels < 250 mg/dL. The prevalence of euglycemic DKA is increasing with the popularity of ketogenic (low-carbohydrate) diets. We present herein the case of a patient with newly diagnosed type 1 DM who developed euglycemic DKA following a ketogenic diet. A 22-year-old woman presented to the emergency department with malaise, fatigue, nausea, and vomiting. She had no family history of DM. She had consulted her primary care physician 2 weeks before due to hair loss, numbness, and tingling sensation in her fingertips. Her fasting blood glucose was 205 mg/dL at that time. Reluctant to use medication to control her blood glucose levels, she started a ketogenic diet. On admission, she was conscious, oriented, cooperative, and tachycardic. Her body mass index was 17.6 kg/m2. Laboratory tests showed fasting blood glucose of 86 mg/dL, glycated hemoglobin of 10.3%, and elevated insulin levels. Ketone levels in urine and blood were high, indicating ketosis. High anion-gap metabolic acidosis was detected, with a pH of 7.10 and serum bicarbonate level of 12 mEq/L. A diagnosis of new-onset DM and euglycemic DKA was established. She was treated with a modified DKA protocol that included intravenous dextrose-containing serum as fluid therapy, and intravenous insulin infusion was delayed until blood glucose levels increased above 250 mg/dL. The development of euglycemic DKA in our patient was attributed to severe carbohydrate restriction. This case underscores the importance of considering dietary risk factors, particularly ketogenic diets, in the management of DM.