We prepared 2,3,5,6,7,8-hexasilabicyclo[2.2.2]octan-1-yl-substituted biphenyl, terphenyl, and tolan, and observed that introduction of the polysilacage group into arenes induced bathochromic shifts of absorption maxima and enhancement of molecular extinction coefficients, compared with the parent π-conjugated arenes, in addition to increase in fluorescence quantum yields.