This study evaluates the safety and immunogenicity of live attenuated vaccine in adults aged 50 years and older. Half of participants will receive high doses of the vaccine,while the other half will receive low doses of the vaccine in phase I clinical trial. At the phase II clinical trial, participants will be distributed equally to four groups(low、middle, high doses of the vaccine and placebo).

Inclusion Criteria:

• Adults 50 years and older,no vaccine contraindications;
• Subject to comply with the requirements of clinical trial programs;
• No immune globulin vaccination history within a month, no vaccination history within 28 days;
• Axillary temperature ≤37.0 ℃;
• Patients with chronic diseases should be in stable ;
• Postmenopausal or female subjects is no longer the possibility of pregnancy, or subjects pregnancy test was negative and has no pregnancy planner during the clinical trial period;
• The value of blood routine (WBC, RBC, Hb) is normal , or abnormal but meaningless by clinicians judgment ;
• Alanine aminotransferase (ALT) values is normal, or abnormal but meaningless by clinicians judgment ;
• Renal function (serum urea nitrogen) is normal, or abnormal but meaningless by clinicians judgment.

Exclusion Criteria:

• Allergies, seizures, epilepsy, encephalopathy and other medical history or family history of mental illness;
• Subjects who is allergic to any element of the vaccine,and have a history of severe allergy to any vaccine;
• Subjects who is suffering from immune deficiency, receiving immunosuppressive therapy or immunocompromised due to HIV;
• Subjects who had a history of herpes zoster five years ago;
• Varicella or herpes zoster vaccination history;
• Pregnant or lactating women;
• Women who are planning a pregnancy in the near future;
• Any prior administration of vaccine in last 28 days or planned to vaccinate any vaccine during the observation period;
• Suffering from acute febrile diseases, and infectious diseases;
• Thrombocytopenia or other coagulation disorder history, which may cause subcutaneous taboo;
• Accept any other investigational drug users within two months;
• Subjects had high fever (axillary temperature ≥38.0 ℃) in the past three days ;
• The value of blood routine (WBC, RBC, Hb) is abnormal and meaning by clinicians judgment ;
• Alanine aminotransferase (ALT) values is abnormal and meaning by clinicians judgment ;
• Renal function (serum urea nitrogen) is abnormal and meaning by clinicians judgment.
• Blood pressure is abnormal after medication control;
• Known or suspected diseases including: respiratory diseases, acute infection or chronic disease , and cardiovascular disease, kidney disease, skin disorders in the acute phase;
• Any condition that in the opinion of the investigator, may interfere with the evaluation of study objectives.