The city-county dispatching automation integrated system and distribution network dispatching automation system have been successfully developed and applied in some areas.But there is still some duplicated work to do in both systems，including model and diagram maintenance，data acquisition for some substations and basic network analysis applications.In order to resolve these problems，a technical support system of distributed city-county distribution automation based on dual-core structure is put forward.This structure maintains the relative independence of city-county dispatching automation integrated system and distribution network dispatching automation system，and adopts distributed data acquisition technology to realize unified data acquisition.It also adopts automatic model clipping to realize main station model sharing，integrated monitoring，integrated simulation training and integrated automatic voltage control.