Abstract: A dynamic and non-persistent mapping resource aggregation mechanism was proposed, through which functional-driven workflow system was formed in SOA (service oriented architecture)environment for application aggregation requirement. In the mechanism, services in application model were not static component. Application process model and task were separated and functions needed by application were concerned. The mechanism consisted of three layers: In the bottom layer, service information collection was created to aggregate all services of same functionality needed by application; In the middle layer, function attributes of services was defined; In the top layer, application context was created to realize constrains between services and binding conditions while implementing task. In the model, logic data was adopted to maintain data relation between services for heterogeneous service interfaces. Through the mechanism, application was composed by functions needed. A workflow system based on the mechanism, NGGWf (national geology grid workflow),has been applied in geologic applications in NGG(national geology grid) environment.