The invention relates to a method for preparing a PET (Polyethylene Terephthalate) engineering plastic particle of attapulgite fast crystallization. The particle is applied to various industries such as aviation, trains, other traffic and transportation systems and the like. The method comprises the following technical steps of: (1) modifying the surface of attapulgite; (2) adding the modified attapulgite in the step (1) to ethylene glycol, stirring, dispersing, adding terephthalic acid, the modified attapulgite and the ethylene glycol dispersion liquid into an esterification kettle for esterification, adding ethylene glycol antimony as a catalyst, mixing, stirring, introducing the mixture into a polycondensation kettle, reacting and discharging to obtain an attapulgite / PET fast crystallization particle; and adding the attapulgite / PET fast crystallization particle into a twin-screw extruder, simultaneously drying and introducing glass fiber into the twin-screw extruder, cooling with water after extrusion, and granulating. The invention has simple technology and low additive addition quantity, a fast crystallization nucleating agent is evenly distributed over a polyester PET macromolecule by a copolymerization mode, and the product performance is greatly improved.