An embodiment of the present invention discloses a monitoring system and method for a metering device. The monitoring system includes a monitoring device; the monitoring device includes a metering cabinet monitoring terminal and a metering box monitoring terminal; the metering cabinet monitoring terminal is used to obtain door opening information of a metering cabinet and control action of a circuit breaker according to the door opening information of the metering cabinet; the metering box monitoring terminal is configured to obtain door opening information of a metering box and control actionof the circuit breaker according to the door opening information of the metering box. The invention provides a monitoring device for the metering device. When a door of the metering device is opened,legality of door opening is determined via the monitoring device according to the door opening information; when the door is opened illegally, the circuit breaker is controlled to trip so as to prevent the lawbreakers from stealing electricity and ensure safety.