The catalytic dehydrocoupling of bis(1-sila-3-butyl)benzene 1 and 2-phenyl-1,3-disilapropane 2 by $Cp_2ZrCl_2$/Red-Al and $Cp_2ZrCl_2$/n-BuLi was reported to compare their catalytic efficiency. The dehydrocoupling of monomeric silanes 1 with the $Cp_2ZrCl_2$/Red-Al and $Cp_2ZrCl_2$/n-BuLi combination catalysts produced two phases of polymers: one is a highly cross-linked insoluble solid, and the other is noncross-linked or slightly cross-linked soluble oil and could be a precursor for the solid polymer. The dehydrocoupling of 2 with the $Cp_2ZrCl_2$/n-BuLi combination catalyst similarly produced two phases of polymers. By contrast, the catalytic reaction of 2 with the $Cp_2ZrCl_2$/Red-Al combination catalyst produced a soluble polymer via redistribution/dehydrocoupling process.