The invention belongs to the field of high polymer materials and discloses a water scour-resistant superhydrophobic composite fiber membrane and a preparation method and application thereof. A composite fiber membrane is prepared into high polymer fibers by adopting a hydrophobic high polymer material through an electrospinning technology; homogeneous or heterogenic hydrophobic high polymer material solution coats the fiber membrane through an electrospinning technology; the composite fiber membrane is subjected to physical or chemical crosslinking treatment, and finally the superhydrophobic composite fiber membrane which is composed of the fibers and microspheres and has the surface provided with a micro-nano structure is obtained. The diameters of the fibers in the water scour-resistant superhydrophobic composite fiber membrane are 100 nm to 20 [mu]m, and the microsphere dimension is 1-30 [mu]m. The micro-nano structure formed by the fibers and the microspheres in the composite fiber membrane is fixed, so that the water scour-resistant superhydrophobic composite fiber membrane has excellent superhydrophobic and scour-resistant performances, can be applied to the fields such as oil-water separation, self-cleaning, antifreezing and antibiosis and have a huge economic benefit potential.