Abstract: Geospatial service servers over traditional networks such as "Client/Server" can not collaborate with each other just like some isolated islands.As the number of geospatial servers increases,the scalability of "Client/Server" networks also proves to be a major hurdle.A decentralized network based on P2P to conquer those barriers is presented.In the proposed model,super geo-peer,basic geo-peer and inferior geo-peer are used to express super geospatial service server,normal geospatial service server and geospatial service consumer respectively.A system cost model,which is the function of the size ratio between super geo-peers and basic geo-peers,is presented to get an appropriate optimal size ratio and makes the system’s search performance optimal.Based on the above work,an optional management algorithm is also proposed to construct a decentralized network system.