The invention relates to a preparation method of anti-ultraviolet anti-pilling polyester slices. The preparation method comprises an esterification reaction working procedure and a polymerization reaction working procedure, wherein the esterification reaction working procedure comprises a primary esterification reaction section and a secondary esterification reaction section; in the primary esterification reaction section, aliphatic dicarboxylic acid and/or non-para-aryl dicarboxylic acid are/is introduced to serve as a third monomer; in the secondary esterification reaction section, flexiblepolyethylene glycol is introduced to serve as a fourth monomer; after esterification is completed, a hindered amine light stabilizer and a hindered phenol antioxidant which are respectively prepared from acetic acid and ethylene glycol as a solvent and hydroxy silicone oil are added; and after prepolymerization and before final polymerization in the polymerization reaction working procedure, an ultraviolet absorbent is added. The polyester fibers spun from the polyester slices prepared by the method provided by the invention have excellent anti-ultraviolet and anti-pilling performances; and after the polyester fibers are knitted/woven into knitted/woven fabric, test shows that the fabric has the following correlated technical indexes: the ultraviolet light transmittance is not more than 5.0%, and the anti-pilling performance is not less than 4-level.