Fifty-six years old male type 2 diabetes patient with fasting blood sugar (FBS) 414 mg/d and hemoglobin A1c (HbA1c) 10.7% tried low carbohydrate diet (LCD) 30 days. After the diet, his FBS decreased to 174 mg/d and HbA1c was 7.7%. Therefore, he escaped from insulin injection and was able to treat with metformin.