The invention discloses a preparation method of a disperse dye capable of alkaline dyeing. The preparation method comprises the following step of carrying out a substitution reaction of a compound VI and a compound X-R2, wherein R1 is -H, -CH3, -C2H5, -OCH3 or -OC2H5, and R2 is C1-C4 straight-chain or branched-chain alkyl or benzyl, R8 is C1-C4 straight-chain or branched-chain alkyl, nitro, -NHCOCH3 or -NHCOC2H5, R9 and R10 are independently -H, halogen or nitro, and X is halogen. The disperse dye obtained by the preparation method shows a bright yellow color, can be used individually, also can be in combination use with alkali-resisting disperse dyes having other colors, and has excellent alkali resistance and hydrogen peroxide oxidization resistance stability.