This is an multicenter, randomized, double-blind, parallel-controlled study to evaluated the efficacy of pioglitazone hydrochloride and metformin hydrochloride tablets on the patients with newly diagnosed type 2 diabetes mellitus combined with non-alcoholic fatty liver disease.

Taking metformin monotherapy as a control, we evaluated the efficacy of pioglitazone hydrochloride and metformin hydrochloride tablets on hepatic fat ultrasound and liver enzyme levels, and observed whether the drug can improve fatty liver in patients with newly diagnosed type 2 diabetes combined with non-alcoholic fatty liver disease. This is an multicenter, randomized, double-blind, parallel-controlled study.

Inclusion Criteria:

1. To meet the new diagnosed type 2 diabetes patients, never received oral hypoglycemic drugs or insulin therapy;
2. In accordance with the nonalcoholic fatty liver (NAFLD) criteria for the diagnosis of patients.
3. the level of HbA1c was 7 -10.0%;
4. age 18-70, body mass index 21-35kg/m2;
5. the subjects informed consent and signed the informed consent.

Exclusion Criteria:

1. type 1 diabetes or secondary diabetes;
2. suffering from other liver diseases, such as hepatitis, self - free liver, etc.
3. abnormal thyroid function (in the active period), or the need for long-term oral and intravenous glucocorticoids to treat patients;
4. patients with severe renal dysfunction or renal disease (eGFR<60);
5. in those with abnormal liver function, Alanine transaminase(ALT) or Aspartate transaminase(AST) was more than 3 times the normal upper limit.
6. people with serious gastrointestinal diseases such as peptic ulcers and chronic diarrhea;
7. patients with severe cardiopulmonary disease, cerebrovascular disease or stents;
8. hemopoietic system diseases such as serious primary diseases, hemoglobin < 100g/L or need regular transfusion treatment;
9. pregnant, breast-feeding, women of childbearing age who are unwilling to contraception during the study period;
10. chronic cardiac insufficiency, the classification of heart function III level and above;
11. uncontrolled malignant tumor, and the history of bladder cancer.
12. acute complications of diabetes;
13. the use of other drugs for diabetes and liver disease;
14. patients who had participated in other clinical studies within three months;
15. people who have known allergies to this kind of drugs are known.
16. it is impossible to guarantee the effect or the safety judgment of the drug or the person who is unable to cooperate with the mental illness.