NB-IoT(Narrow Band Internet of Things)is a new IoT technology. It has wide coverage, low power consumption, low data transmitting speed and huge amount of connection. It can be applied in many kinds of electrical application including AMI (Advanced Metering Infrastructure). This paper analyzes the feasibility of using NB-IoT in AMI system and describes an applied mode of NB-IoT based on the infrastructure of AMI system, current communication technologies and NB-IoT in the gas meter and water meter pilot performance test. The deployment scenarios and methods for NB-IOT in AMI system are obtained. This paper also proposes monitoring methods receiving sensitivity, co-channel interference and adjacent channel interference.