The fabrication of fibrillated cellulose fibers and their utilization have been of more interest recently because of their biodegradability, low cost, and mechanical and thermal properties comparable to those of glass fibers or carbon fibers. in this study, we applied the combination of a mechanical shearing process with a cooling system and an enzymatic pretreatment to produce fibrillated cellulose fibers from softwood pulps. The effects of the mechanical shearing process, the cooling system, and the enzymatic treatment on the formation of the fibrillated cellulose fibers its well as physical and mechanical properties of paper were investigated. It was indicated that the cooling system was necessary in the grinding process to prevent the adverse effect of heat generation oil mechanical properties of paper sheets. It was observed that the enzyme-assisted mechanical shearing process improves the production of fibrillated cellulose fibers and results in a substantial improvement of tensile strength and elongation of paper while producing thinner and less bright paper with low water absorptiveness.