The invention discloses a preparation method of a rapid molding 
powder material used for three dimensional printing. The method is characterized in that the method comprises the following steps: 1, 
powder material pretreatment: mixing 88-96% of a 
powder material with 4-12% of 3-aminopropyltriethoxysilane, and 
grinding at a rotating speed of 500-1000rpm for 2-6h to obtain a pretreated powder material; and 2, molding material preparation: adding 50-70% by 
mass of water, adding 0.5-1.0% of 
polyethylene glycol monooleyl 
ether, stirring for dissolving, adding 2-10% of 
polyvinyl alcohol, heating for dissolving, adding 25-40% of the pretreated powder material, stirring for uniform mixing, putting the obtained mixture in a grinder, carrying out normal temperature mixing 
grinding for 10-15h, and carrying out 
spray drying to obtain the rapid molding powder material. The rapid molding powder material can be directly molded at a temperature of 85-100DEG C under a pressure of 1-10MPa without sprinkling a binder, and has the advantages of simple preparation technology, easy condition control, low production cost and easy industrialized production.