The IEC 61850 series defines the abstract data model and service model in an object-oriented method， and also the mapping onto specified protocols such as manufacturer message specifications（MMS） and so on. Four kinds of data structure during IEC 61850 implementation are analyzed. The capabilities of supporting the service models by IEC 61850 of the four data structures are compared. It is concluded， as the comprehensive-data structure not only accords with the current protocol mapping but also supports the changes of future model and the extension of protocol mapping， that it has broad application prospects.