EipponCell MHEC LH 660M methyl hydroxyethyl cellulose is utilized in cement slurry plaster, and its viscosity increases continuously. The molecular network structure of cellulose ether intertwines with the network structure of cement hydration products. The initial hydration of cement indirectly raises the concentration of cellulose ether, resulting in a "composite superposition effect" on the viscosity of cellulose ether solution and cement slurry. Consequently, the viscosity of the modified cement slurry with cellulose ether is significantly higher than the sum of their individual viscosities. Both cellulose ether modified cement slurry and pure cement slurry exhibit shear thinning or pseudoplastic behavior. The pseudoplasticity of cellulose ether modified cement slurry is lower compared to that of pure cement slurry. At lower rotation rates or with lower viscosity of cellulose ether modified cement slurry or lower cellulose ether content, the pseudoplasticity of cellulose ether modified cement slurry becomes more pronounced. As the temperature rises, the speed and extent of cement hydration increase, leading to a gradual increase in viscosity of pure cement slurry. The viscosity of modified cement paste, however, varies with temperature due to the different inhibitory abilities of various types and amounts of cellulose ethers on cement hydration.