The purpose of this work was to develop the high-performance ultra-high molecular weight polyethylene(UHMWPE) fibers reinforced rigid polyurethane (RPU) composites. UHMWPE fibers were electroless deposited bycopper to form the copper oxides on the fiber surface. The results showed that the copper oxides-coated UHMWPE fibershad the positive effects on the mechanical properties of the composites. Compared with neat RPU, the tensile strength,tensile modulus, bending strength, and impact strength of copper oxides-coated UHMWPE fibers/RPU composites wereincreased by 20.4 %, 39.7 %, 11.0 % and 15.8 %, respectively. Interlaminar shear strength (ILSS) was also increased by14.9 %. The dynamic mechanical analysis (DMA) proved the reinforcing effect of copper oxides-coated UHMWPE fibers. Both strength and toughness were increased mainly due to the metal oxides deposited on the fiber surface. On one hand, thecopper ions and oxygen ions on the UNMWPE fiber surface could react with oxygen and hydrogen in polyurethane to formchemical bonds. On the other hand, the copper oxides increased the crack propagation path to improve the toughness of thematerial.