A grommet

A widened tube portion is provided between a first (11) and a second small-diameter tube portions (12) provided at the opposite sides of a grommet (10,10') with respect to longitudinal direction. The first small-diameter tube portion (11) is provided at a front part with respect to insertion direction into a through hole (9). A cut-away portion (15) is formed to extend forward from a rear end surface of the widened tube portion (13) continuous with the second small-diameter tube portion (12). The widened tube portion (13) is branched into an outer tube (13c) and an inner tube (13d) continuous with the second small-diameter portion (12). A slanted wall (16a) and a vertical wall (16b) are formed to project from the outer circumferential surface (13b-2) of a portion of the outer tube (13c) located more backward than the back end of the cut-away portion (15) while being opposed to each other, thereby forming a body locking recess (16). A back end position of the cut-away portion is located more radially inward than the base end of the slanted wall (16a), and an opening side of the cut-away portion (15) located radially inwardly of the vertical wall (16b) has an outer circumferential surface which is slanted to widened toward an opening end.