The invention discloses a fluidized bed catalyst for preparing propylene from methanol and a preparation method of the fluidized bed catalyst. The preparation method comprises the steps of firstly carrying out effective dispersion and ball-spraying forming on ZSM-5 molecular sieve raw powder by virtue of a dispersing agent, and then modifying the formed catalyst by virtue of one or more salt solutions in nonmetal and rare earth metals through a dipping method, so as to obtain the fluidized bed catalyst. The fluidized bed catalyst has the beneficial effects that the dispersing agent is low in cost and is easily available, and the preparation method of the catalyst is simple; the fluidized bed catalyst is applied to a fluidized bed reaction for preparing propylene from methanol, when the reaction temperature is 500 DEG C and the weight hourly space velocity of methanol is 4h<-1>, the conversion rate of methanol is more than 99%, and the selectivity of propylene is more than 46%.