The connection between the power plant supervisory information system（SIS） and simulator and the simulation application of SIS data are described. The combination of SIS and power plant simulation is of great significance for the security and economical operation of the power plant. The connection mode of the SIS and the power plant simulation system is designed in the course of application. The corresponding interface software is developed and the SIS data is combined with simulator application. Actual application of a number of power plants has verified that the simulation system under the SIS environment can not only achieve faster and more vivid machine simulation development， but also provide a good method for personnel training in on-the-spot failure analysis and fault recurrence.