To provide a damping sheet capable of enhancing a restraining effect of a lightweight floor impulsive sound.

This damping sheet 11 has a structure of successively laminating a first sheet member 12 composed of span bond type nonwoven fabric, a second sheet member 13 formed in a sheet shape by keanding asphalt of 50 to 60 wt.% and cast iron powder of 40 to 95 wt.% generated when shot-blasting a cast iron casting, and a third sheet member 14 by backing a cushioning layer 14b composed of polyester fiber of areal density 100 to 350 g/m coated with acrylic resin with the span bond type nonwoven fabric 14a. The impulsive sound generated in a floor is damped by the cushioning layer 14b of the damping sheet 11. Since vibrational energy trying to pass through into the second sheet member 12 caused by the impulsive sound is damped by being converted into heat energy by internal friction of the cast iron powder and the asphalt, the restraining effect of the lightweight floor impulsive sound of the damping sheet 11 is enhanced.