Single-phase watt-hour meter supporting two-way communication

The invention provides a single-phase watt-hour meter supporting two-way communication. The watt-hour meter comprises a main control CPU (Central Processing Unit), a data acquisition unit, a data processing unit, a display unit and a communication device interface, wherein the data acquisition unit is used for acquiring a voltage signal and a current signal from a power line; the data processing unit is used for processing the acquired voltage signal and the acquired current signal and generating voltage quality information and electric energy metrical information; the display unit is used for displaying the voltage quality information and the electric energy metrical information; the communication device interface is used for connecting with a communication device; one of a plurality of communication devices in different communication systems is selected to be connected with the communication device interface and used for sending the voltage quality information and the electric energy metrical information to