The invention discloses a lining bag in favor of thick liquid discharge. The lining bag comprises a lining bag body, a discharge outlet and a pouring opening, wherein the pouring opening is in sealing connection with the lining bag body, and the liquid is poured into the lining bag by the pouring opening; the discharge outlet is in sealing connection with the lining bag body, and the liquid is discharged out of the lining bag by the discharge outlet; the lining bag is used for storing the liquid, and the lining bag body has elasticity, so that when the liquid is poured, the surface area of the lining bag body is increased and the volume of the lining bag is increased along with the pouring of the liquid; when the liquid is discharged, the surface area of the lining bag body is reduced and the volume of the lining bag is reduced along with the discharging of the liquid. By adopting the lining bag, the use ratio of the liquid, particularly the thick liquid, is increased favorably, waste is reduced, and cost is lowered; meanwhile, the actions of manually extruding and discharging residual liquid are omitted, and labor is saved.