Abstract: The present invention relates to the technical field of catalyst preparation, and discloses a preparation method of a Ziegler-Natta catalyst. The method includes the following steps: subjecting magnesium halide, alcohol and an electron donor to a first contact reaction in the presence of an inert solvent to obtain a magnesium halide alcoholate and performing first cooling; subjecting titanium halide to second cooling; subjecting the cooled titanium halide, the cooled product containing the magnesium halide alcoholate and an electron donor to a second contact reaction; filtering the product of the second contact reaction to obtain the Ziegler-Natta catalyst; and subjecting the Ziegler-Natta catalyst and the heated titanium halide to a third contact reaction. The method has the advantages such as short cycle, high efficiency, etc., being suitable to industrial production.