The invention discloses an ammeter accessorial device which comprises an acquisition unit, an electricity fee calculating unit, a user identity identification unit and a GSM communication unit. The acquisition unit collects electricity quantity consumption information from user ammeters; the input end of the electricity fee calculating unit is connected with the acquisition unit and the GSM communication unit, and is used for receiving the current electricity quantity consumption information, real-time electricity fee standard and settled electricity quantity values, and calculating electricity fee sum to be paid by the user currently based on the current electricity quantity consumption information, the real-time electricity fee standard and the settled electricity quantity values; the user identity identification unit is responsible for checking the information of the users requesting for table look-up, and transmitting passed user instructions to the acquisition unit and the fee calculating unit; and the GSM communication unit is connected with the user identity identification unit and the electricity fee calculating unit and establishes communication with a user mobile phone and a power supply service center. Through the device, one-to-one ammeter-mobile phone communication is established, so that the users can check the table through the mobile phones anytime and anywhere, and can know the electricity quantity consumption information of themselves; convenient and quick effects are realized; and electricity quantity consumption plans can be made reasonably, and electric energy waste and unnecessary electricity fee expenditure can be prevented.