EipponCell HEMC LH4000 Cellulose ether is a widely used admixture in industrial drymix mortar, significantly impacting the rheological properties of the mortar. Increasing the content of cellulose ether results in an initial torque increase in the mortar. However, after a stirring period, the flow resistance of the mortar decreases instead. When the initial fluidity remains relatively constant, the fluidity loss of the mortar initially decreases and then increases. In comparison to starch ether and thickened powder, cellulose ether exhibits higher viscosity and stability, enhancing its yield strength and overall performance in mortar applications.