A grommet 1, which is configured to be attached to a hole 10a in a panel 10, includes a cylindrical body 2 having along its entire periphery a locking recess 3 that is locked into the hole 10a. Also, on an outer surface of the body 2, there is provided two first ribs 8 spaced from each other and extending from one end of the body 2 to the other end of the body 2, and two second ribs 7. These first ribs 8 are provided on one side with reference to a virtual plane that includes a central axis P and an alternate long and two short dashes line Q. The second ribs 7 are provided on the other side with reference to the virtual plane. Also, a width of the first rib 8 is larger than that of the second rib 7.