A metallocene compound represented by the following Chemical Formula 1: ##STR00001## wherein M is a transition metal of Group 4; Cp denotes a cyclopentadienyl ring unsubstituted or substituted by hydrogen, alkyl, cycloalkyl, aryl, alkenyl, alkylaryl, arylalkyl or arylalkenyl radicals; Qs, which are the same or different, are halogen radicals, alkyl, alkenyl, aryl, alkylaryl, or arylakyl radicals having 1 to 20 carbon atoms, or alkylidene radicals having 1 to 20 carbon atoms; A' is methoxymethyl, t-butoxymethyl, tetrahydropyranyl, tetrahydrofuranyl, 1-ethoxyethyl, 1-methyl-1-methoxyethyl, or t-butyl; and a is an integer of 4 to 8. The metallocene compounds in this invention can be strongly supported on the inorganic support, and the supported catalyst of this invention allows for an olefin polymerization process without any fouling in the reactor, and produces a polymer with better morphology and bulk density.