There are provided; (i) a solid catalyst component obtained by contacting a trivalent titanium atom-containing solid catalyst component precursor (C) with a halogeno compound (A) of the 13 or 14 group of elements in the periodic table of the elements and an electron donor (B), or a solid catalyst component obtained by contacting an intermediate product with a titanium-halogen bond-carrying compound (D), the intermediate product being obtained by contacting the solid catalyst component precursor (C) with a halogeno compound (A′) of the 14 group of elements in the periodic table of the elements and the electron donor (B), or a solid catalyst component comprising a magnesium atom, a titanium atom, a halogen atom and an electron donor and having a relative surface area of not more than 30 m2/g, the catalyst component being superior in a particle form, and (ii) a catalyst comprising the solid catalyst component and an organoaluminum compound, the catalyst being high in polymerization activity.