Two kinds of 2.5D deep straight-joint structure ultra-high molecular weight polyethylene(UHMWPE)(twisted and original) fibers woven fabric reinforced epoxy resin composites were prepared by the hand lay-up method. Subsequently, the flexural property, microstructures, and failure mechanisms of the composites were also investigated. The average flexural strength of 2.5D deep bend-joint structure twisted fiber and original fiber woven fabric composites were 176.66 MPa and 204.45 MPa, respectively. The results of the characteristics indicated that the twist was the main factor which affected the flexural performance. Flexural property vitally relied on the strength of the fiber itself. Twist decreased the strength of the yarns, which meant that when the mechanical property of woven fabric reinforced composites was improved, the yarns must be kept straight in the woven fabric. The study are extremely valuable to guide the improvement of the mechanical property of the woven fabric reinforced composites. The two kinds of 2.5D deep straight-joint structure ultra-high molecular weight polyethylene (UHMWPE) (twisted and original) fibers woven fabric reinforced epoxy resin composites were prepared by the hand lay-up method. failure mechanisms of the composites were also investigated. The average of flexural strength of 2.5D deep bend-joint structure twisted fiber and original fiber woven fabric composites were 176.66 MPa and 204.45 MPa, respectively. The results of the characteristics indicated that the twist was the main factor which affected the flexural performance. the flexural property vitally relied on the strength of the fiber itself. twist decreased the strength of the yarns, which meant that when the mechanical property of the woven fabric reinforced composites was improved, the yarns must be kept straight in the woven fabric. The study are extremely valuable to guide the improvement of the mechanical property of the woven fabric reinforced composites.