In an ultrarapid-release current-limiter electrical switch comprising at least a support with a stationary contact, at least a movable contact borne by an arm rotatably mounted in a movable unit and submitted to the action by a spring reacting against the movable unit, and a control mechanism with a control lever, an oscillatable lever kept stopped by a release device, a toggle lever system between said movable unit and said oscillatable lever and an extension spring acting between said control lever and the hinge of said toggle lever system, said support of the stationary contact and said movable contact bearing arm defining, under contact closure conditions, two portions parallel and close to each other in the current path, wherein currents of opposite sign flow, which are suitable to produce, in case of strong current intensities due to short-circuits, repulsive electrodynamic forces; between said movable contact bearing arm and said release device for the oscillatable lever of the control mechanism mechanical means are interposed suitable to cause, on a displacement of said arm by eletrodynamic repulsion, directly the release of said oscillatable lever.