The invention discloses a cladding method for compounding tungsten carbide on a high-chromium cast iron roller shell and belongs to the field of laser cladding. The cladding method for compounding tungsten carbide on the high-chromium cast iron roller shell comprises the following steps: step 1, carrying out ultrasonic and dye penetrant inspection treatments; step 2, preheating the whole roller shell to the range of 200-300 DEG C before cladding; step 3, mixing a nickel-based powder with a spherical tungsten carbide powder in a certain ratio to form a spherical tungsten carbide composite nickel-based powder; step 4, feeding the spherical tungsten carbide composite nickel-based powder for cladding, and selecting such parameters as a laser powder of 3.5-4.2kW, a scanning speed of 500-700mm/min, a spot diameter of 3-5mm and a total cladding layer thickness of 3-5mm; and step 5, fully preserving heat for 10-15 hours after the completion of cladding, and carrying out grinding and coping after cooling. The cladding method for compounding tungsten carbide on the high-chromium cast iron roller shell has the following advantages: a synchronous laser cladding method is adopted to implement cladding to the high-chromium cast iron after the nickel-based alloy powder is combined with the tungsten carbide, and the obtained cladding layer thus is high in hardness and good in wear resistance; moreover, a substrate and the cladding material are fused mutually in a transition area, and the binding strength is high without stripping easily, and further, the service life is prolonged.