A method for preparing a catalyst component for ethylene polymerization, comprising the steps of: dissolving a magnesium halide in a solvent system comprising an organic epoxy compound and an organic phosphorus compound, the solvent system optionally but preferably further comprising an inert diluent, to form a homogeneous solution; adding an alcohol compound before, during or after the formation of the homogeneous solution, to finally form a magnesium halide-containing solution; contacting the solution obtained from the step with a titanium compound, with a silicon compound being added before, during or after the contacting, to form a mixture; heating the mixture slowly to a temperature of from 60 °C to 110 °C and maintaining at that temperature for a period of time, solids gradually precipitating during the heating; and recovering the solids formed in the step, to obtain a catalyst component, wherein: the alcohol compound is a linear or branched alkyl or cycloalkyl alcohol with 1 to 10 carbon atoms, or an aryl or aralkyl alcohol with 6 to 20 carbon atoms, the alcohol compound being optionally substituted by halogen atom(s); the titanium compound has a general formula Ti a X b, in which R is a C 1 -C 14 aliphatic or aromatic hydrocarbyl, X is a halogen, a is 0, 1 or 2, b is an integer of from 1 to 4, and a+b=3 or 4; and the silicon compound is an organic silicon compound having a general formula R 1 x R 2 y Si(OR 3) z, in which R 1 and R 2 are independently a hydrocarbyl or a halogen, R 3 is a hydrocarbyl, 0≤x≤2, 0≤y≤2, 0≤z≤4, and x+y+z=4. dissolving a magnesium halide in a solvent system comprising an organic epoxy compound and an organic phosphorus compound, the solvent system optionally but preferably further comprising an inert diluent, to form a homogeneous solution; adding an alcohol compound before, during or after the formation of the homogeneous solution, to finally form a magnesium halide-containing solution; contacting the solution obtained from the step with a titanium compound, with a silicon compound being added before, during or after the contacting, to form a mixture; heating the mixture slowly to a temperature of from 60 °C to 110 °C and maintaining at that temperature for a period of time, solids gradually precipitating during the heating; and recovering the solids formed in the step, to obtain a catalyst component, wherein: the alcohol compound is a linear or branched alkyl or cycloalkyl alcohol with 1 to 10 carbon atoms, or an aryl or aralkyl alcohol with 6 to 20 carbon atoms, the alcohol compound being optionally substituted by halogen atom(s); the titanium compound has a general formula Ti a X b, in which R is a C 1 -C 14 aliphatic or aromatic hydrocarbyl, X is a halogen, a is 0, 1 or 2, b is an integer of from 1 to 4, and a+b=3 or 4; and the silicon compound is an organic silicon compound having a general formula R 1 x R 2 y Si(OR 3) z, in which R 1 and R 2 are independently a hydrocarbyl or a halogen, R 3 is a hydrocarbyl, 0≤x≤2, 0≤y≤2, 0≤z≤4, and x+y+z=4. the alcohol compound is a linear or branched alkyl or cycloalkyl alcohol with 1 to 10 carbon atoms, or an aryl or aralkyl alcohol with 6 to 20 carbon atoms, the alcohol compound being optionally substituted by halogen atom(s); the titanium compound has a general formula Ti a X b, in which R is a C 1 -C 14 aliphatic or aromatic hydrocarbyl, X is a halogen, a is 0, 1 or 2, b is an integer of from 1 to 4, and a+b=3 or 4; and the silicon compound is an organic silicon compound having a general formula R 1 x R 2 y Si(OR 3) z, in which R 1 and R 2 are independently a hydrocarbyl or a halogen, R 3 is a hydrocarbyl, 0≤x≤2, 0≤y≤2, 0≤z≤4, and x+y+z=4.