In this study, we aimed to obtain bamboo fibers suitable for pulp molding production by using unbleached bamboo chemical pulp as the research subject. The impact of fiber fractionation technology on its performance was investigated. The research content includes the effects of fiber fractionation methods on fiber morphology, fiber appearance, and drainage performance. Additionally, the impact of filtration-based fiber fractionation on the physical properties and oil resistance of fiber-formed paper was studied. The results indicate that using a 14-mesh filtration-based fiber fractionation technique effectively removes non-fibrous cells and fine fibers. After fractionation, the average fiber length increased from 1.596 mm to 1.792 mm, and the drainage performance of the pulp was significantly improved. The burst index of the bamboo fiber handsheets increased by 12.75%, the tear index by 13.55%, and the tensile strength by 17.3%. The oil resistance grade of the bamboo fiber handsheets, when adding 2.5% oil repellent, increased by 3 times, and when adding 3% oil repellent, increased by 1.16 times. We believe that our results shed light on future bamboo pulp materials suitable for pulp molding products.