The invention discloses a surface-modified nano boron fiber / Mo-Zn-S-F composite material. A preparation method of the surface-modified nano boron fiber / Mo-Zn-S-F composite material comprises the following steps: S1, putting molybdenum chloride, zinc chloride, ammonium sulfide and ammonium hexafluorophosphate into a water bath reaction kettle, adding a reaction solvent, performing hydrothermal reaction at 180-220 DEG C for 15-20 hours, cooling to room temperature, performing suction filtration, washing with benzene for 3-5 times, then washing with water for 4-7 times, then washing with ethanolfor 5-8 times, drying the obtained product in a vacuum drying oven at the temperature of 60-80 DEG C for 6-8 hours, grinding, and sieving with a 200-300-mesh sieve to obtain Mo-Zn-S-F; S2, dispersingthe Mo-Zn-S-F and the nano boron fibers prepared in the step S1 into a high-boiling-point solvent, then adding polymethyltriethoxysilane modified epoxy resin into the high-boiling-point solvent, carrying out stirring reaction for 6-8 hours at the temperature of 60-80 DEG C, then carrying out precipitation and suction filtration in water, and washing for 3-5 times by using ethanol so as to obtain the surface modified nano boron fiber / Mo-Zn-S-F composite material. The wear-resistant packing prepared from the composite material has the advantages of mechanical property, wear resistance, high temperature resistance, good chemical stability and excellent sealing property.