PURPOSE: To reduce the number of parts and cost and to improve workability at the time of assembly by integrally molding rail parts and decorative frame of a synthetic resin material, then sloping the top edges of the rail parts to incline the height of the rail parts from one side in the longitudinal direction thereof toward the other end side.

CONSTITUTION: The rail 11 is an integrally molding formed by extrusion of a synthetic resin such as vinyl chloride. An outer wall 15 and an inner wall 16 which constitute the decorative frame 14 are erected parallel to the outside of the rail parts 12, 13 and thin soft fins 17, 18 which seal the spacing with a sliding door are provided to the top ends of the wall 15 and the wall 16. Three pieces of grooves 19, 20, 21 are formed between the walls 15, 16 and the rail parts 12, 13. A drain hole 22 is provided through the bottom of the groove 21 and mounting holes 20a are provided to the bottom of the groove 20. The sloped parts 23, 24 formed to the upper edges of the respective rail parts 12, 13 are provided by diagonally cutting the rail parts 12, 13 after extrusion and are so formed as to intersect with each other in the central part in the longitudinal direction.