The purpose of this study is to evaluate the effects and mechanism of mosapride citrate on diabetic gastroparesi.

To evaluate the effect of mosapride on DPG by 13 C - octylic acid breath test.

IF C13- octylic acid be absorbed by mucous membrane of small intestine, octylic acid will be oxidated to CO2.Patients eating food containing C13, and then collect their expired gas at 15, 30,45,60,75,90,105,120,150,180,210,240min, analyse the mass of C13 by mass spectrometer, then can calculate the gastric emptying rate.

Inclusion Criteria:

1. 18≤ age ≤ 75
2. Patients coincided to, the WHO diagnostic criteria for diabetes in 1999 (namely have diabetes symptoms, plasma glucose tendency for 11.1 / L, at any time or fasting plasma glucose tendency for 7.0 / L, or oral glucose tolerance test 2 h plasma glucose levels tendency for 11.1 / L）
3. fasting blood-glucose≤7.0mmol/L and 2h postprandial plasma glucose≤10.0mmol/L
4. Be diagnosed diabetes more than 5 years, blood sugar steady in one month.
5. have the following symptoms for over 4weeks: early satiety ,postprandial fullness ,nausea, vomting,abdominal distension,belching, inappetence, epigastric pain, constipation.
6. Be diagnosed as Delayed Gastric Emptying by C13 breath test.
7. Signed informed consent.

Exclusion Criteria:

1. take gastrointestinal drugs within 2 weeks prior to screening. Or patients with other digestive disease.
2. All patients will be administrated gastroscope in order to exclude stomach or duodenum disease, pyloric obstruction. It's normal in Liver, gallbladder, pancreas,spleen, nephridium by Ultrasound examination .
3. Serious ketoacidosis.
4. History of abdominal operation.
5. Thyroid hypofunction or hyperthyroidism.
6. nervous system disease or autoimmune diseases.