The aim of the study is to investigate the efficacy and safety of premixed insulin treatment in patients With type 2 diabetes mellitus using professional and personal Flash Glucose Mornitoring.

Professional and personal Flash Glucose Mornitoring will be used in patients with type 2 diabetes who are treated with premixed insulin. The frequency of hypogycemia and the blood glucose control will be analyzed by flash glucose mornitoring once a month for 3 months and doctors will adjust the hypoglycemia treatment according to the results every month. HbA1c, glycemic variation, beta-cell function and androgen levels will be measured.

Inclusion Criteria:

1. participate voluntarily and sign the subject informed consent before the test.
2. for patients with type 2 diabetes who met WHO1999 diagnostic criteria, subcutaneous injection with premix insulin Bid/Tid, single drug and/or combination of oral hypoglycemic drugs, the treatment regimen was stable for more than 2 months.
3. no acute complications such as diabetic ketoacidosis and diabetic hyperosmolar syndrome.
4. subjects are able and willing to undergo FGM examination, diet and exercise regularly.

Exclusion Criteria:

1. patients treated with GLP-1 agonist in the last 3 months
2. patients who are allergic to insulin.
3. impaired liver and renal function, ALT 2.5 times higher than the upper limit of normal value;Serum creatinine was 1.3 times higher than the upper limit of normal.
4. a history of drug abuse and alcohol dependence within the past 5 years.
5. used systemic hormone therapy in recent 3 months.
6. patients with poor compliance and irregular diet and exercise.
7. patients with infection and stress within four weeks.
8. patients who cannot tolerate flash glucose mornitoring.
9. patients who are pregnant, nursing or or preparing to become pregnant.
10. any other apparent condition or comorption as determined by the investigator, such as severe heart and lung disease, endocrine disease, neurological disease, tumor disease, other pancreatic disease, history of mental illness.