A solid catalyst component for the (co)polymerization of α-olefins having general formula (I): ZrnMAlxClyMgp  (I) wherein: M represents titanium (Ti), vanadium (V), or mixtures thereof; n is a number ranging from 0.01 to 2; x is a number ranging from 0.1 to 4; y is a number ranging from 5 to 53; p is a number ranging from 0 to 15; obtained by means of a process comprising putting at least one zirconium arene in contact with at least one metal compound and, optionally, with at least one compound of magnesium. Said solid catalyst component can be advantageously used as a solid component in a catalyst for the (co)polymerization of α-olefins.Said catalyst can be advantageously used in a process for the (co)polymerization of α-olefins.