In an upper side sealing portion, an upper side water guide groove is formed between an outer sealing lip and an inner sealing lip. In a vertical side sealing portion, a vertical side water guide groove extending to a position below a door opening/closing device is formed between a vertical side attachment portion and a vertical side sealing lip. The upper side water guide groove is disposed at a cabin inner side of an outer panel of a frame. An upper end of the vertical side water guide groove is disposed at the cabin inner side of the outer panel. A portion of the vertical side water guide groove located above the door opening/closing device extends downward from an upper end, and extends to a cabin outer side relative to an inner panel of a frame.