The work aims to prepare plant fiber suspension system by mechanical stirring of renewable plant fiber, explore the factors affecting the rheology of the fiber suspension and the dispersion and orientation of the fiber in the system, so as to lay a foundation for the processing and transportation design of subsequent industrial products. The effects of fiber mass fraction, aspect ratio (fiber length), temperature and water-soluble polymer on the rheological properties of the system were tested by rotary rheometer. The fiber suspension system was a non-Newtonian fluid, showing shear thinning. The change of viscosity of solution with temperature was in line with Arrhenius equation through linear fitting. The increase of fiber mass fraction and aspect ratio (fiber length) would increase the apparent viscosity of the system, promote the dispersion of fibers and the formation of network structure, while the viscosity would decrease exponentially with the increase of temperature. The addition of water-soluble polymer PVA and polyacrylamide dispersant would improve the viscosity of the system and help to disperse the fiber; The higher the alcoholysis degree of PVA, the more hydrophilic groups, and it was easy to generate more hydrogen bonds with the fiber, forming a fiber network structure, which was helpful for the subsequent foam structure control. The higher the alcoholysis degree, the easier gel. Cationic CPAM could improve the negative charge on the fiber surface, destroy the electrostatic adsorption of the fiber, and make the fiber disperse more evenly. Factors such as fiber mass fraction, aspect ratio (fiber length), and system temperature will affect the rheological properties of fiber suspension. The addition of water-soluble PVA and dispersant polyacrylamide can help to disperse the fiber, which is of reference significance for the industrial fiber slurry proportioning process. At the same time, the viscous flow characteristics of the system are convenient for the equipment design of the slurry conveying system of the production line.