<p>Disclosed is a cellulose-based filter aid with high turbidity removal capability, and a manufacturing method thereof. This method of manufacturing a filter aid involves (A) grinding and/or thermochemically treating a cellulose-containing biomass to obtain a pre-treated biomass, (B) a step for treating with cellulase the pre-treated biomass obtained in step (A) to obtain a cellulase-treated product, and a step (C) for obtaining the solid component of the cellulase-treated product of step (B). This cellulose-based filter aid contains the water-insoluble cellulase-treated product of a cellulose-containing biomass.</p>
