The invention provides a freeze-dried preparation containing fosaprepitant and a preparation method of the freeze-dried preparation. The freeze-dried preparation contains an active ingredient and other carriers, wherein the active ingredient is an effective amount for treatment of fosaprepitant dimeglumine, and the other carriers include a solubilizing agent, a complexing agent and a freeze-drying excipient; before freeze-drying, an acidity regulator is used for regulating the pH value of a liquid medicine to be 6.5-9.5; and the solubilizing agent is selected from one or more of polyethylene glycol dodecahydroxyl lithium stearate, hydroxypropyl-beta-cyclodextrin and polyethylene glycol. The freeze-dried preparation containing fosaprepitant, provided by the invention, is stable in property and low in hemolysis rate, and improves the compliance of clinical medication of patients.