Patient description: A 67-year-old healthy woman came to the clinic to have her flu shot in early October. She works at a rehab center and has no underlying disease. It is her first vaccination this year. she is menopausal and has 4 children. She does not some. She takes daily multivitamins and anti-hypertensive drugs. She exercises regularly for 30 minutes a day at least 5 days a week. She has no allergies to any food or drugs.

Clinical trial eligibility criteria: eligible ages (years): 30.0-999.0,  Hepatitis E Criteria(all volunteers): 1. Aged over 30 years old on the day of enrollment 2. Axillary temperature is below than 37.0 ℃. 3. No administration of HEV vaccine before the study 4. Judged as healthy and eligible for vaccination by the investigators through a selfreported medical history and some physical examinations. 5. Able to understand this study information and willing to comply with all study requirements. 6. Willing to participate in this study and sign informed consent form. 7. Negative serological markers for hepatitis E Criteria(experiment group): 1. ALT < 1.5×ULN 2. No spleen swelling,no cirrhosis and no hepatocellular carcinoma Criteria(control group): 1. HBsAg(-)  With clinical evidence of malignant tumor 2. History of severe cardio-cerebrovascular disease 3. Administration of hepatotoxicity drugs before or during the study 4. Pregnancy,breast-feeding or plan to be pregnant in 7 months later 5. Participated in any other clinical trial during the study period. 6. Use of any investigational product or non-registered product (drug or vaccine)within 30 days preceding the first dose of the study vaccine or plan to use during the study period. 7. Received immunosuppressed, immunoregulation therapy or corticosteroid systemic therapy for more than 14 days in the 6 months before entry, except local treatment. 8. Administration of any immunoglobulin or blood products within 3 months preceding the first dose of the study vaccine,or plan to use during the study period. 9. Administration of any inactivated vaccines within 14 days preceding the first dose of the study or attenuated live vaccines within 21 days preceding the first dose of the study. 10. Had a fever (axillary temperature over 38°C) within 3 days or acute illness requiring systemic antibiotics or antiviral treatment within 5 days before vaccination. 11. Immunodeficiency (such as HIV carriers), primary disease of important organs, malignant tumor, or any immune disease (such as systemic lupus erythematosus, arthritis pauperum, splenectomy or functional asplenia or other disease which might affect immune response). 12. History of allergic disease or history of serious adverse events occurring after vaccination, i.e., allergy,urticaria, dyspnea, angioneurotic edema or abdominal pain. 13. Allergic history to any component of this vaccine. 14. Asthma that needed emergency treatment, hospitalization, oral or intravenous corticosteroid to keep stable in the past two years. 15. Combining another severe internal medicine disease(such as severe hypertension, cardiopathy,diabetes and hyperthyroidism) 16. Anomal coagulation function or coagulopathy diagnosed by doctor 17. Epilepsy(not including alcohol epilepsy within 3 years prior to abstinence and simple epilepsy that do without curing within 3 years prior to the study ) 18. Anomal psychology or mind affecting the individual's ability to obey the study requie 19. Other medical, psychological, social or occupational factors that, according to the investigators' judgment,might affect the individual's ability to obey the protocol or sign the informed consent