To compare the effects of different initial insulin dose regimens during the short-term insulin intensive treatment on time to glycemic goal, hypoglycemia prevalence, glycemic variability and other safety problems in newly diagnosed type 2 diabetes mellitus(T2DM) patients, in order to investigate the rational of formula based initiation regimen.

Diabetes has become one of the major chronic non-communicable diseases. Its prevalence was rising in these years. Short-term intensive insulin therapy can improve the β-cell function and nearly half of the patients can live with long-term glycemic remission. It has therefore become the recommended treatment for the newly diagnosis T2DM patients with high blood glucose. However, due to the glycemic goal for intensive therapy is strict, it's important to find out a suitable initial insulin regimen for continuous subcutaneous insulin infusion(CSII) with which patients can achieve euglycemia safely, stably and rapidly. In previous study, the investigators found out that the total daily insulin dose at the first day when euglycemia was achieved（TDD-1） was associated with weight, waist circumference, triglycerides and fasting blood glucose levels. According to this, the investigators figured out a formula for estimation of insulin dose for the short-term intensive insulin therapy in patients with newly diagnosed T2DM. However, its feasibility needs to be further verified. Therefore, the investigators conducted this prospective randomized controlled study to compare the effects of different initial insulin dose regimens during the short-term insulin intensive treatment on time to glycemic goal, hypoglycemia prevalence, glycemic variability and other safety problems in newly diagnosed type 2 diabetes patients, in order to investigate the rational of formula based initiation regimen.

Inclusion Criteria:

• Newly diagnosed type 2 diabetes (1999 World Health Organization standard);
• Type 2 diabetic patients who have never received any hypoglycemic therapy (including oral hypoglycemic agents, Chinese medicine , and insulin);
• Body mass index (BMI) between 20-35 kg/m2;
• Fasting plasma glucose (FPG) levels between 7.0 -16.7 mmol/L, glycated haemoglobin >7.0%;
• Willing to receive CSII intensive treatment during hospitalization and monitoring blood glucose 8 times per day.

Exclusion Criteria:

• Type 1 diabetes or special type of diabetes;
• Acute complications of diabetes: ketoacidosis, hyperosmolar coma, lactic acidosis, etc.;
• Severe macrovascular complications: acute cerebral vascular accidents, acute coronary syndromes, peripheral arterial disease requiring vascular intervention or amputees for hospitalization occur within 12 months before selection;
• Severe microvascular complications: proliferative phase retinopathy; urinary albumin excretion rate(AER)> 300 mg/g or urinary protein Positive, quantitative> 0.5 g/d; uncontrolled painful diabetic neuropathy and significant diabetic autonomic neuropathy;
• Obvious liver and kidney dysfunction: alanine aminotransferase ≥ 2.5 times the upper limit of normal, total bilirubin ≥ 1.5 times the upper limit of normal, serum creatinine greater than 150 umol/L or creatinine clearance less than 50 mL/min;
• Significant increase in blood pressure: blood pressure continued to be higher than 180/110 mmHg;
• Significant anemia: hemoglobin <100g /L may require regular blood transfusions;
• Use of drugs that may affect blood glucose during 12 weeks, such as oral/intravenous corticosteroids, growth hormone, estrogen/progestogen, high-dose diuretics, antipsychotics, etc. Low-dose diuretics for antihypertensive purposes (hydrochlorothiazide <25 mg/d, indapamide ≤ 1.5 mg/d), and physiological quantities of thyroid hormones used for replacement therapy are not limited to this;
• Effects associated with other underlying diseases influenced the observation of blood glucose, such as systemic infection or severe comorbidity, malignancy or chronic diarrhea, uncontrolled endocrine gland function abnormalities, chronic cardiac insufficiency (grade III and above), psychosis, or pregnant;
• The patients does not cooperate, or the investigator judges that it may be difficult to complete the study.