The invention discloses a high-strength corrosion-resistant stirrer blade and a manufacturing method thereof. The stirrer blade comprises a blade body, wherein a plurality of through holes are uniformly formed on the surface of the blade body; and the outer side of the blade body is coated with an ultrahigh molecular weight polyethylene powder layer. The stirrer blade is manufactured by putting a cast steel stirrer blade into a mould, coating the stirrer blade with the ultrahigh molecular weight polyethylene powder, and then performing mould pressing, calcining and forming the stirrer blade. The manufactured stirrer blade which is coated with ultrahigh molecular weight polyethylene is high in strength, abrasion-resistant, high in corrosion resistance, economical and practical; the service life of the manufactured stirrer blade is more than two years; the manufactured stirrer blade is difficult to corrode in a natural environment and has a good stirring function; and the manufactured stirrer blade has the advantages of high weather resistance, fatigue resistance, electrical insulation and the like; therefore, the manufactured stirrer blade can be produced in batches as industrial products, the maintenance cost, the repair cost and replacement cost of the stirrer blade can be greatly reduced, and the manufactured stirrer blade has an industrial application value.