Haemophilus influenza type b (Hib) remains a serious global health threat associated with high mortality and morbidity in young children. In China, The overall impact of Hib-related infections and the extent of coverage of Hib conjugate vaccines are unclear.Generally, vaccination has been considered the most effective way to prevent infection against Hib.In order to evaluate safety and immunogenicity of a haemophilus influenzae type b (Hib) conjugate vaccine developped by Chengdu Olymvax Biopharmaceuticals Inc. a phase III clinical trial is planned to conduct in healthy infants and children in China.