The present invention relates to a catalyst component for polymerization of an olefin comprising a compound represented by the Fischer projection of: wherein R5 is substituted or unsubstituted hydrocarbyl having 1 to 20 carbon atoms; R6 and R7 are different and independently selected from the group consisting of hydrogen, halogen and substituted or unsubstituted hydrocarbyl having 1 to 20 carbon atoms; R5-R7 optionally containing one or more hetero-atoms replacing one or more carbon atoms, one or more hydrogen atom or both, wherein said hetero-atom is selected from the group consisting of nitrogen, oxygen, sulfur, silicon, phosphorus and halogen; and wherein the compound of Formula (I) is the only internal electron donor in the catalyst component. The present invention also relates to a process for preparing a polymerization catalyst component comprising the steps of i) contacting a compound R4zMgX2-z wherein R4 is aromatic, aliphatic or cyclo-aliphatic group containing 1 to 20 carbon atoms, X is a halide, and z is in a range of larger than 0 and smaller than 2, with an alkoxy- or aryloxy-containing silane compound to give a first intermediate reaction product; ii) contacting the first intermediate reaction product with at least one activating compound selected from the group formed by internal electron donors and compounds of formula M(OR2)v-w(R3)w, wherein M can be Ti, Zr, Hf, Al or Si, each R2 and R3, independently, represent an alkyl, alkenyl or aryl group, v is the valency of M and w is smaller than v and iii) contacting the second intermediate reaction product with a halogen-containing Ti-compound and an internal electron donor represented by the Fischer projection of formula (I); and optionally with at least one compound selected from a group comprising a monoester, a diester and a 1,3-diether.