Silica supported MgCl2-CP2MCl2 (M=Ti or Zr) catalysts (Si-Mg-M) were prepared by deposition of a homogeneous solution of a metallocene and anhydrous magnesium chloride in tetrahydrofuran (THF) onto a high surface area silica (SiO2). Catalyst thus prepared show higher polymerization activity when compared to metallocenes supported on either silica or magnesium chloride alone. The molecular weight and polydispersity of the poly(ethylene)s obtained from metallocenes supported on SiO2-MgCl2 were found to be higher and narrower, respectively, relative to silica or MgCl2 supported metallocene catalysts. (C) 2002 Society of Chemical Industry.