The invention discloses a soft-base abrasive belt and belongs to the technical field of surface treatment. The soft-base abrasive belt of the invention comprises an annular band-shape abrasive belt; the abrasive belt comprises a soft base layer, a bonding layer and a sand grain layer; the bonding layer is laid on the surface of the soft base layer; the surface of the bonding layer is provided with the sand grain layer formed by multiple sand grains. The soft-base abrasive belt of the invention is mainly used for solving the problem that grindings are liable to produce obstruction and is difficult to eliminate; by the installation of netted grinding discharging grooves, grindings can be conveniently discharged; the grinding discharging grooves increases from the middle to two sides of the abrasive belt so that the discharge of grindings is better. The soft base layer is made of fiber rubber material so as to greatly increase the service life; the structure is simple and the application scope is wide; the soft-base abrasive belt is suitable for promotion.