To provide a support cover excellent in durability and capable of being easily mounted, and a sound insulation wall which is excellent in durability and beauty and fitted with the support cover.

The support cover 4, covering a flange section of an H-shaped support 3, is provided with a cover body for covering the surface of the flange in a width direction. The outer surface of the cover body is formed in such a curved shape as to swell outward, and both ends, in a width direction, of the cover body are provided with locking parts engaged with the side edge section of the flange. Additionally, the support cover 4 is mounted on at least one flange of the sound insulation wall, and the end of a wall member 6 is inserted into a groove part 8 formed of the web and flange of the H-shaped support 3 for the purpose of making the wall member 6 supported on the H- shaped support 3.