Catalyst component for olefin polymerization, preparation method therefor and use thereof

A catalyst component for olefin polymerization, wherein the catalyst component comprises elemental magnesium, elemental titanium, and an internal electron donor;

• the internal electron donor comprises a phosphate ester, and an α-cyanosuccinate and/or a substituted α-cyanosuccinate, a molar ratio of the phosphate ester to the elemental magnesium is (0.0002-0.002):1.

A method for preparing a catalyst component for olefin polymerization, wherein the method comprises:

• mixing a magnesium-containing carrier, titanium halide, and an internal electron donor, wherein the internal electron donor comprises a phosphate ester, and an α-cyanosuccinate and/or a substituted α-cyanosuccinate, the phosphate ester, and the magnesium-containing carrier are used in amounts such that the molar ratio of the phosphate ester in the obtained catalyst component to the magnesium-containing carrier calculated in terms of elemental magnesium is (0.0002-0.002):1.