The invention discloses a super-hydrophobic filter screen and a preparation method thereof. The super-hydrophobic filter screen comprises a
metal screen, wherein a plurality of
boron nitride nanotubesgrow on the surface of the
metal screen; the roots of the
boron nitride nanotubes are perpendicular to the surface of the
metal screen; the diameters of the roots of the
boron nitride nanotubes is larger than the diameters of the tops of the
boron nitride nanotubes; and the parts, close to the tops, of the
boron nitride nanotubes are conical, and the other parts of the
boron nitride nanotubes arecylindrical. The method comprises the following steps: mixing
boron oxide powder and
magnesium powder according to a
molar ratio of (1: 1.5)-(1: 2.5), placing the obtained mixture in a container, placing a metal net at the central position of the upper part of the container, and placing the container in a tubular
atmosphere protection annealing furnace; and introducing
inert protective atmosphereinto a furnace tube of the tubular
atmosphere protection annealing furnace; and when the temperature rises to 300-500 DEG C, stopping introducing
argon, introducing high-purity
ammonia gas, continuing heating to 1200-1300 DEG C, keeping the temperature for 2-12 hours, then stopping introducing the high-purity
ammonia gas, introducing
inert protective
atmosphere, and carrying out natural cooling to
room temperature to obtain the high-temperature-resistant
corrosion-resistant super-hydrophobic filter screen.