For example, a weatherstrip is mounted on an opening edge of a vehicular body side opening section opened or closed by means of a vehicular trunk in order to secure a sealing characteristic. This weatherstrip 30 includes a welt section 32 in a substantially letter U shape in cross section and fitted to a flange 31 mounted on a peripheral edge section of the vehicular body side opening section and a trim lip 34 extended from an outer surface of this welt section 32 and which covers and hides an end edge of vehicular body trim 33. This trim lip 34 causes the end edge of vehicular body trim 33 not to be exposed and an outer appearance quality is improved. Welt section 32 is provided with holding lips 35, 35 extended toward obliquely a summit section from an inner surface of the respective side wall sections mutually connected from the summit section. When these holding lips 35 are elastically contacted on flange 31, welt section 32 is held by flange 31 (for example, refer to a Patent document 1).