Investigators determined to detect the effect of smeglutide on body weight and metabolic indexes among overweight and obese participants through two different dosing programs.

Participants will be randomized into either group. One group will start from 0.25mg per week for four weeks, then increase to 0.5mg per week for four weeks, and 1mg per week maintenance dose for 8 weeks. The other group dosage regime depends on the tolerance of the semaglutide from participants. The dosage will stabilize on the dose how much participant could tolerate. At the end of 16 weeks treatment, comparison will be carried out on weight change before and after treatment and (1) Comparison of different administration methods (standards and titrations) on participant compliance, appetite and quality of life improvement; (2) Comparison of metabolism (waist hip circumference, body fat and body composition, blood pressure, blood lipid, blood glucose, insulin resistance) in different administration modes; (3) Comparison of adverse reactions of metabolic drugs in different administration modes.

Inclusion Criteria:

1. 18 ≤ age<75;

2. Overweight or obesity: meet either one of the following standards

   1. Patients with BMI ≥ 24 kg/m2 and at least one obesity complication (hypertension, hyperlipidemia, apnea syndrome, cardiovascular disease)
   2. Simple obese patients with BMI ≥ 28kg/m2
   3. Abdominal obesity, waist circumference ≥ 90 cm for males and ≥ 80 cm for females

Exclusion Criteria:

1. Have a personal or family history of medullary thyroid carcinoma (MTC) or have multiple endocrine neoplasia type 2 (MEN-2) patients.
2. Patients with severe hypersensitivity to smeglutide or any other excipient component.
3. Diabetic patients (glycosylated hemoglobin ≥ 6.5% or fasting blood glucose ≥ 7.0 mmol/L or blood glucose ≥ 11.1 mmol/L 2 hours after meal or random blood glucose ≥ 11.1 mmol/L).
4. Triglyceride>5.6mmol/L;
5. Participants in other clinical drug trials in recent three months.
6. The range of weight change in recent 90 days is>5kg.
7. Cushing's syndrome and abnormal thyroid function.
8. Pregnant or breastfed women.
9. The study doctor judged that it was not suitable to participate in the test.