A method for producing an olefin polymerization catalyst includes bringing a solid catalyst component for olefin polymerization, a vinylsilane compound, an organosilicon compound, and an organoaluminum compound into contact with each other in an inert organic solvent under an inert gas atmosphere in the absence of a specific vinyl compound, wherein a washing treatment is not performed after the vinylsilane compound has been added to the reaction system, the solid catalyst component includes a magnesium compound, a titanium halide compound, and an electron donor compound that does not include a phthalic acid ester structure, and includes a diol skeleton, and the organosilicon compound does not include a vinyl group, and includes at least one group selected from an alkoxy group and an amino group.