The utility model provides the interlock control circuit structure of a dual-supply automatic change-over switch apparatus, which comprises a first molded case circuit breaker, a second molded case circuit breaker, an interlock module, a switch control module and a control module. The interlock module comprises a first interlock relay and a second interlock relay. The switch control module comprises a first closing relay and a second closing relay. The control module comprises a single-chip microcomputer, a first closing position feedback circuit and a second closing position feedback circuit. According to the technical scheme of the utility model, two functions of electrical interlock and signal output can be realized through one switch position signal. Meanwhile, the electrical interlock is realized in a signal transfer manner. The electrical interlock signal is controlled by a DC low-voltage signal. Therefore, the implementation method in the prior art by means of 220V AC signals is no longer adopted. The safety of signals is improved.