The invention discloses a primary-secondary information model sharing system for an electricity SCADA (supervisory control and data acquisition) system. The primary-secondary information model sharing system comprises a CIM (common information module) model, an SCD (substation configuration document) model, a model mapper and a mapping dictionary. The mapping dictionary defines a mapping relation between the CIM module and the SCD model; the model mapper is arranged between the CIM model and the SCD model; when a request side sends a request to a response side, the model mapper reads configuration information of the mapping dictionary, sends the information to the response side and transmits return information of the response side to the request side. By the primary-secondary information model sharing system, the problem about information interaction among systems based on IEC61850 or IEC61970 standards can be solved, and information models and instance maintenance results of station sides can be directly shared to scheduling sides, so that repeated working of scheduling personnel can be avoided, and working efficiency is improved.