To provide a weatherstrip of an automobile, easily installed in a cross-sectional substantially U-shaped retainer, without slipping out after installation.

This weatherstrip for the automobile is installed by pushing the other side heel part 12 of an installation base part 10 in the other side groove part 22 of the retainer 20, after inserting one side projection part 11 of the installation base part 10 into one side recessed part 21 of the cross-sectional substantially U-shaped retainer 20. A plurality of notch parts 13 are intermittently formed in the longitudinal direction in the other side heel part 12, and the notch part 13 and a remaining part 14 are alternately arranged, and the other side heel part 12 is easily pushed in the other side groove part 22.