With a large number of smart meters installation, the power utility can get a variety of information such as meter metering device via a communication network. Considering the needs of grid state estimation for metering device, we propose a general security domain model. The algorithm of calculating the network security domain by using metering device is designed in this paper. Through the security domain model and AHP in obtaining network security at the same time measuring device, given the state of metering devices affect the reliability of the key factors is estimated to improve the state estimation accuracy.