To provide a superior soundproof wall capable of coping with a low frequency sound with various kinds of huge facilities as a sound source, and easy in construction work even if the wall is constituted in the relatively low height causing no environmental deterioration.

This soundproof wall is arranged on a propagation passage of noise, and is characterized by forming a wall surface as a gentle slope, and imparting acoustically almost soft properties of becoming almost zero in surface sound pressure to the wall surface. Even the soundproof wall having the relatively low height can largely secure the area of the acoustically softly formed wall surface, and can cope with the low frequency sound with the various kinds of huge facilities as the sound source, and does not cause the environmental deterioration such as deteriorating ventilation, and hindering visibility.