A weather strip comprises an extruded portion and a molded portion which is integrally connected to a longitudinal end portion of the extruded portion. The extruded portion includes a sealing portion formed by extrusion molding from a sponge rubber, soft thermoplastic elastomer or sponge thermoplastic elastomer, and an attachment portion having a separable core member embedded therein and formed by co-extrusion molding from a solid rubber, low foamed rubber or thermoplastic elastomer. The molded portion comprises a sealing portion formed of a soft thermoplastic elastomer or spongy thermoplastic elastomer, and an attachment portion formed of a semi-rigid resin.