Evaluate the preliminary effectiveness and safety of the Gastric Bypass Stent System in treating nonalcoholic fatty liver disease.

The Gastric Bypass Stent System is intended to be used in Patients with Diagnosis of nonalcoholic fatty liver disease， Proton density fat fraction measured by magnetic resonance imaging (MRI-PDFF) ≥8%. In this pivotal, prospective, single-arm clinical investigation the Sponsor seeks to demonstrate the safety and performance of the Gastric Bypass Stent System in Treatment of Patients with Nonalcoholic Fatty Liver Disease

Inclusion Criteria:

（ - ） Males or females with age between 18 and 65 years old;

（ - ） Diagnosis of nonalcoholic fatty liver disease;

（ - ） Proton density fat fraction measured by magnetic resonance imaging (MRI-PDFF) ≥8%;

（ - ） BMI≥24;

Patients who understand the objective of the study; voluntarily participate in the study and have signed the informed consent form; and are able and willing to comply with all requirements, including follow up and evaluations.

Exclusion Criteria:

（ - ） History of excessive alcohol consumption (alcohol consumption equivalent to ethanol > 30 g/d for males and > 20 g/d for females);

（ - ） End-stage liver disease (e.g. hepatic cirrhosis or hepatic cancer) or other conditions which may lead to fatty liver;

（ - ） Unable to cooperate to complete MR examination;

（ - ） Subjects who have used any nonsteroidal anti-inflammatory drug or corticosteroid in the past month;

（ - ） Patients with iron deficiency or iron deficiency anemia;

（ - ） ALT or AST increased to 8 × upper limit of normal (ULN), and bilirubin increased to 2×ULN;

（ - ） Patients with coagulation disorder or haemorrhagic diathesis (platelets <100×109/L);

（ - ） Patients with duodenal ulcer, or previous or existing pancreatitis;

（ - ） History of liver abscess;

（ - ） History of gallstones (symptomatic or presenting of any stone with a diameter greater than 20mm);

（ - ） Patients with gastrointestinal hemorrhage or potential hemorrhage;

（ - ） Gastrointestinal tract anomalies, such as gastrointestinal tract atresia or any or other conditions that would result in failed placement in the gastrointestinal tract;

（ - ） Patients with history of intestinal obstruction or related disease in the past year;

（ - ） Drug abusers or patients with uncontrollable psychiatric disorders;

（ - ） Patients with any contraindication to endoscopy based on the investigator's judgment;

（ - ） Pregnancy or lactating women;

（ - ） Patients who are participating in any other drug or medical device clinical study;

（ - ） Patients with any other conditions evaluated by the investigators as unsuitable for participating in the trial;