PURPOSE: To enable replacement only of skin by pivoting one end of skin supporting member to the door inner board and stopping the other end of skin supporting member dis-mountably to the door inner board while applying the skin member to said skin supporting member.

CONSTITUTION: The lower end of skin supporting member 2 is pivoted to a rising 12 formed at the lower end of door 1 inner board 11 and the upper end 22 of skin supporting member 2 is stopped to brackets 14, 15 formed on the inner board 11 while applying a bag-shaped skin member 3 on the skin supporting member 2. Then the upper portion 31 of skin member 3 and skin supporting member 2 are covered with west section skin 6 while the lower section 32 is stopped by a door pocket member 7. The arm rest body 41 is applied with an arm rest pad 42 while the regulator 51 is fixed with a regulator handle 5. With such structure, only the skin member 3 can be replaced easily by removing the skin supporting member 2.