An electromagnetic switching device, comprising: a junction box having an accommodating space formed to be one side open by side plates and a bottom plate; and a relay having fixed contacts and movable contacts within a casing and detachable to and/or from the accommodating space, wherein: the junction box includes a pair of protrusions which are protruded from the side plates toward an opposite side to the accommodating space respectively, and provided on an opposite side of each other, characterized in that the relay includes a lever which is hinge-coupled to the casing and caught by the pair of protrusions, the lever is configured to press the relay toward the bottom plate when rotating in one direction, and to move the relay away from the bottom plate when rotating in other direction opposite to the one direction, the lever comprising a handle and a pair of lever plates vertically extended from both ends of the handle respectively such that one of the pair of lever plates face other of the pair of lever plates, the pair of lever plates are configured to couple to side walls of the casing by a hinge coupling portion and to couple to the pair of protrusions respectively, and wherein each of the pair of lever plates includes a pair of arc-shaped slit having a convex shape, and the pair of lever plates includes a pair of ribs respectively, wherein each of the pair of ribs protrudes out of two portions (290a, 290b) forming one end of the arc-shaped slit to a direction that is opposite to where the casing is located such that the each of the pair of ribs connects the two portions (290a, 290b) so as to support the two portions (290a, 290b). a junction box having an accommodating space formed to be one side open by side plates and a bottom plate; and a relay having fixed contacts and movable contacts within a casing and detachable to and/or from the accommodating space, wherein: the junction box includes a pair of protrusions which are protruded from the side plates toward an opposite side to the accommodating space respectively, and provided on an opposite side of each other, characterized in that the relay includes a lever which is hinge-coupled to the casing and caught by the pair of protrusions, the lever is configured to press the relay toward the bottom plate when rotating in one direction, and to move the relay away from the bottom plate when rotating in other direction opposite to the one direction, the lever comprising a handle and a pair of lever plates vertically extended from both ends of the handle respectively such that one of the pair of lever plates face other of the pair of lever plates, the pair of lever plates are configured to couple to side walls of the casing by a hinge coupling portion and to couple to the pair of protrusions respectively, and wherein each of the pair of lever plates includes a pair of arc-shaped slit having a convex shape, and the pair of lever plates includes a pair of ribs respectively, wherein each of the pair of ribs protrudes out of two portions (290a, 290b) forming one end of the arc-shaped slit to a direction that is opposite to where the casing is located such that the each of the pair of ribs connects the two portions (290a, 290b) so as to support the two portions (290a, 290b). the junction box includes a pair of protrusions which are protruded from the side plates toward an opposite side to the accommodating space respectively, and provided on an opposite side of each other, the relay includes a lever which is hinge-coupled to the casing and caught by the pair of protrusions, the lever is configured to press the relay toward the bottom plate when rotating in one direction, and to move the relay away from the bottom plate when rotating in other direction opposite to the one direction, the lever comprising a handle and a pair of lever plates vertically extended from both ends of the handle respectively such that one of the pair of lever plates face other of the pair of lever plates, the pair of lever plates are configured to couple to side walls of the casing by a hinge coupling portion and to couple to the pair of protrusions respectively, and wherein each of the pair of lever plates includes a pair of arc-shaped slit having a convex shape, and the pair of lever plates includes a pair of ribs respectively, wherein each of the pair of ribs protrudes out of two portions (290a, 290b) forming one end of the arc-shaped slit to a direction that is opposite to where the casing is located such that the each of the pair of ribs connects the two portions (290a, 290b) so as to support the two portions (290a, 290b).