A holding structure of an intervening member, comprising: a first member; a second member provided parallel to the first member; the intervening member provided between the first member and the second member, and having a supporting plate portion facing the first member or the second member, the supporting plate portion having a through-bore with an axis center extending in a direction perpendicular to the first and second members; characterized in that a wobbling-prevention member is provided between the intervening member and at least one of the first and second members in a compressed state to prevent the intervening member from wobbling; wherein the wobbling-prevention member integrally includes: an axis portion slidably passing through the through-bore of the supporting plate portion, and having one end portion positioned on a side of the first member relative to the supporting plate portion, and the other end portion positioned on a side away from the first member relative to the supporting plate portion; an umbrella elastic head portion integrally provided on the one end portion of the axis portion, with a radius thereof expanding from the one end portion to the supporting plate portion; and a bulging portion formed on the side of other end portion of the axis portion relative to the supporting plate portion and having a radius thereof expanding more than a radius of the through-bore, said bulging portion clamping the supporting plate portion in cooperation with the elastic head portion. a first member; a second member provided parallel to the first member; the intervening member provided between the first member and the second member, and having a supporting plate portion facing the first member or the second member, the supporting plate portion having a through-bore with an axis center extending in a direction perpendicular to the first and second members; characterized in that a wobbling-prevention member is provided between the intervening member and at least one of the first and second members in a compressed state to prevent the intervening member from wobbling; wherein the wobbling-prevention member integrally includes: an axis portion slidably passing through the through-bore of the supporting plate portion, and having one end portion positioned on a side of the first member relative to the supporting plate portion, and the other end portion positioned on a side away from the first member relative to the supporting plate portion; an umbrella elastic head portion integrally provided on the one end portion of the axis portion, with a radius thereof expanding from the one end portion to the supporting plate portion; and a bulging portion formed on the side of other end portion of the axis portion relative to the supporting plate portion and having a radius thereof expanding more than a radius of the through-bore, said bulging portion clamping the supporting plate portion in cooperation with the elastic head portion. an axis portion slidably passing through the through-bore of the supporting plate portion, and having one end portion positioned on a side of the first member relative to the supporting plate portion, and the other end portion positioned on a side away from the first member relative to the supporting plate portion; an umbrella elastic head portion integrally provided on the one end portion of the axis portion, with a radius thereof expanding from the one end portion to the supporting plate portion; and a bulging portion formed on the side of other end portion of the axis portion relative to the supporting plate portion and having a radius thereof expanding more than a radius of the through-bore, said bulging portion clamping the supporting plate portion in cooperation with the elastic head portion.