Roof moulding mounting structure of a vehicle

A roof molding mounting structure of a vehicle is constituted by a groove portion (2) formed along a longitudinal direction of the vehicle, and a roof molding (8) arranged within the groove portion (2). The groove portion (2) is formed in an inverse structure in which a left wall portion (6) and a right wall portion (7) are inward inclined. The roof molding (8) has a head portion (12) positioned above the groove portion (2), a main lip (13) having a front end portion elastically in contact with at least one of the left wall portion (6) and the right wall portion (7) in a lower side of the head portion (12), and a leg portion (15) elastically in contact with a bottom surface of the groove portion (2). The leg portion (15) of the roof molding (8) is elastically deformable in a vertical direction of the groove portion (2), and has a hollow portion.