At the end portion of a wire harness that is connected through a through hole of a casing, a shielding shell is fixed to the casing and covers a connector for a harness attached to the end portion of the wire harness. A grommet covers the outside of the shielding shell. The grommet includes a main portion and a band-fastened portion, and a skirt portion extends from the band-fastened portion. A bundling band fastens the outer circumferential surface of the connecting portion via the band-fastened portion, and the skirt portion is brought into intimate contact with the outer circumferential surface of a step portion that is continuous with the connecting portion. Sealing lips that receive fastening force by the bundling band and come into intimate contact with the outer circumferential surface of the connecting portion in a squeezed state are formed on the inner circumferential surface of the band-fastened portion.