Provided is a grommet that can improve the water-blocking property. A grommet includes an opposing portion 32 that opposes a portion surrounding a mounting hole 12 in a vehicle body panel 11, a first water-blocking portion 33 that extends from the opposing portion 32 and comes in contact with the vehicle body panel 11, and a second water-blocking portion 34 that extends from the opposing portion 32 and comes in contact with the vehicle body panel 11. Each of the first water-blocking portion 33 and the second water-blocking portion 34 is formed in an annular shape that surrounds the mounting hole 12. The second water-blocking portion 34 is provided on the outer circumferential side with respect to the first water-blocking portion 33.