A door weather strip with seal lips attached thereto, fitted to a door sash, and provided with a gap of a given magnitude on a vertical plane between edges of respective seal lips of both an extrusion molded part on the side of a roof and an extrusion molded part on the side of a center pillar, a reinforcing rib is provided over the whole length of a seal lip of a molded part, which connects the extrusion molded parts with each other to form a corner section. The reinforcing rib is located on the interior side of an automobile where no elastic contacts with a body panel is being made, thereby preventing the waving from occurring to the molded part.