Novel silicon substituted PPV derivatives, poly[2,5-bis(trimethylsilyl)-1,4-pheylenevinylene] (BTMS-PPV) and PPV copolymers, were synthesized through water-soluble precursor route, and their electrical and third-order nonlinear optical properties were studied. The BTMS-PPV films could not be doped with 12but doped with FeCI3to show the electrical conductivity of 5.0 × 10−4S/cm. The conductivities of FeCI3−doped copolymer films ranged from 5.0 × 10−1to 25 S/cm depending on their copolymer compositions and draw ratios. The third-order nonlinear optical susceptibility, χ(3)(-ω;ω,ω,-ω), was also investigated by the degenerate four-wave mixing (DFWM) measurement technique at 602 nm. The calculated χ(3)value of BTMS-PPV was 5.8 × 10−10esu. The photoluminescence spectrum of BTMS-PPV was observed and it showed its emission in pure green region.