Address geocoding is a kind of address matching method based on spatial technique. It is the process of transforming a description of a location, such as coordinates, the address or the name of a place, to a location on the earth’s surface. Address geocoding technologies started late in China, many cities just start capturing the geo coding address data. Many topics need to be explored, such as address code structure and geo coding data management. The authors analyzed the current address geocoding rules. The street is regarded as the same level distinct restriction as the courtyard in the current strardards. At this point they think that the spatial characters of the street are weakened. On the basis of relevant national standards, they put forward the definition amendment of city standard address geocoding. In the amendment, as distinct restriction, street becomes independent and is in front of courtyard. Thus, an entity must belong to one street and the address code must contain the street’s code. Usually it is difficult to do address matching with many types of address data because the address data store in different database tables by the entity types. Using streets as spatial reference system, according to the street onward direction, they well integrate the doorplates, address points and parcels together and put forward the new unified street geocoding model: street address chain model. In this model, geocoding is not simple address string matching any more, it also makes well use of the streets’direction, parcels’adjacency and other spatial characters to assist address geocoding process. This can provide model support for future address matching. The example about street address chain model of address geocoding is given. Predictably, this new address geocoding model will improve the match rate and accuracy greatly.