At present, the extent of agricultural information share and exchange is low, especially between different departments or applications where most information resources are separated, scattered and immethodical. In order to integrate agricultural information resources and realize the share and exchange of agricultural information resources, the construction of an agricultural information service system is an effective way. In the paper, combined with the current situation of agricultural informationization construction in China, how to construct the agricultural microorganism information service system is discussed to realize the share and exchange of agricultural information. In order to express various agricultural information, an Agricultural Information Markup Language (AIML) is design that is an XML-based special language for describing agricultural information resources. The system improves the scope and extent of information share and operation coordination by providing common supporting service for operation systems, such as, information exchange service, information security service, etc. Consequently, the whole efficiency of agricultural informationization is enhanced.