A current-limiting device electrically connectable between a power-source-side electric circuit and a load-side electric circuit of a power system so as to limit an overcurrent passing through the power system, comprising: - an electric circuit formation which includes a plurality of contact components which are arranged and can be contacted and separated in such a way that a pair of parallel surfaces are included, and concave engagement portions are formed at side surfaces, and the parallel surfaces are neighbored each other, and a current-limiting resistor which is electrically connected to the plurality of contact components in parallel, in a state where a usual electric circuit is configured in order to pass a usual current between the power-source-side electric circuit and the load-side electric circuit via the plurality of contact components, and a current-limiting electric circuit is configured in order to limit an overcurrent which is passed between the power-source-side electric circuit and the load-side electric circuit; - contact-separation components (12, 17) which include a plurality of engagement protrusions (12a, 17a, 17c) which can be fitted to the concave engagement portions of the plurality of contact components, in a state where the contact-separation components (12, 17) can be shifted between an insertion position at which the engagement protrusions (12a, 17a, 17c) are inserted to the concave engagement portions so as to separate the neighboring contact components each other, and an extraction position at which the engagement protrusions (12a, 17a, 17c) are returned from the insertion position and separated from the contact components so as to contact the neighboring contact components each other; and - a contact driving unit which is electrically connected between the power-source-side electric circuit and the load-side electric circuit in a state where, when the usual current is received from the power system, the contact-separation components (12, 17) are supported at the extraction position so as to configure the usual electric circuit at the electric circuit formation, and when the overcurrent is received from the power system, the contact-separation components (12, 17) are shifted to the insertion position so as to configure the current-limiting electric circuit at the electric circuit formation; characterised in that the engagement protrusions (12a, 17a, 17c) of the contact-separation components (12, 17) are contacted to the concave engagement portions of all contact components which are shifted to the insertion position so as to be separated, even when the contact-separation components (12, 17) are shifted to the extraction position. - an electric circuit formation which includes a plurality of contact components which are arranged and can be contacted and separated in such a way that a pair of parallel surfaces are included, and concave engagement portions are formed at side surfaces, and the parallel surfaces are neighbored each other, and a current-limiting resistor which is electrically connected to the plurality of contact components in parallel, in a state where a usual electric circuit is configured in order to pass a usual current between the power-source-side electric circuit and the load-side electric circuit via the plurality of contact components, and a current-limiting electric circuit is configured in order to limit an overcurrent which is passed between the power-source-side electric circuit and the load-side electric circuit; - contact-separation components (12, 17) which include a plurality of engagement protrusions (12a, 17a, 17c) which can be fitted to the concave engagement portions of the plurality of contact components, in a state where the contact-separation components (12, 17) can be shifted between an insertion position at which the engagement protrusions (12a, 17a, 17c) are inserted to the concave engagement portions so as to separate the neighboring contact components each other, and an extraction position at which the engagement protrusions (12a, 17a, 17c) are returned from the insertion position and separated from the contact components so as to contact the neighboring contact components each other; and - a contact driving unit which is electrically connected between the power-source-side electric circuit and the load-side electric circuit in a state where, when the usual current is received from the power system, the contact-separation components (12, 17) are supported at the extraction position so as to configure the usual electric circuit at the electric circuit formation, and when the overcurrent is received from the power system, the contact-separation components (12, 17) are shifted to the insertion position so as to configure the current-limiting electric circuit at the electric circuit formation;