PURPOSE: In a swing open door associated with door frame for four wheel drive wagon car, to prevent projection of seal and step at joint by projecting fitting chips from open-first door and open-later door while holding a door weather strip between both chips.

CONSTITUTION: A portion of fitting section 15A of open-first door 15 is projected to be flush with the outside face of door to provide longitudinal fitting chip 15B. A portion of fitting section 16A of open-later door 16 is projected from intermediate point of inside and outside faces of door to form a longitudinal fitting chip 16B. Furthermore a door weather strip 14 is fixed to said fitting section 15A and placed between both chips 15B, 16B to perform sealing. With such structure, the fitting section seal will never project into cabin to prevent occurrence of step at the joint between the door frame 13 and door 12 thereby cover cloth window and glass window frame can be shared.