The invention discloses a preparation method of a human VIII blood coagulation factor. The preparation method comprises the following steps: (1) separating cryoprecipitates from
human plasma, and adding a
Tris-HCl dissolving solution to dissolve; (2) primary PEG (
Polyethylene Glycol)
precipitation: adding a PEG 1 solution into the dissolving solution, stirring, standing, and then, centrifuging; (3) collecting a centrifuged suspension liquid, and adding an S / D solution to inactivate; (4) secondary PEG
precipitation: clarifying the inactivated suspension liquid, filtering to obtain a filtrate, transferring the filtrate into a low-temperature reaction tank, adding a PEG 2 solution under the condition of stirring, stirring, standing, and then, centrifuging; and (5) cleaning a precipitate, dissolving the
sediment by using the dissolving solution, centrifuging after complete
dissolution, collecting the suspension liquid, filtering, preparing, degerming, split charging, freeze-
drying, capping, and carrying out
dry heat inactivation to obtain the human VIII blood coagulation factor. A two-step PEG
precipitation method is adopted in the method disclosed by the invention, so that the production process is simplified, and the requirement for large equipment is reduced; the preparation method is small in floor area, simple in operation, low in cost and capable of increasing the labor efficiency and economic benefit.