The reliability of circuit breaker state identification greatly affects the application range of sequence control and remote control. And safety regulations require at least two criteria based on different identical principles and signals to determine the state of the equipment after operation. In this paper, based on the intelligent comparison of current and impedance, comprehensive criterion and warning technology of circuit breaker state is proposed. Based on the injection circuit, the current and voltage of the injected signal are detected and the characteristic change of zero sequence resistance is calculated to realize the on-Line loop impedance monitoring. And the loosing or aging problem of circuit breaker can be found out. While the state monitoring criterion of circuit breaker is proposed, which uses the existing measurement data to constitute the state confirmation criterion.