Stille coupling copolymerization of 1,1-dialkyl-2,5-dibromo-3,4-diphenyl-siloles (R=Et, i-Pr, n-Hex, 1a-c) with bis(tributylstannyl)acetylene in the presence of PdCl₂(PPh₃)₂ catalyst and toluene solvent provided poly[(1,1-dialkyl-3,4- diphenyl-2,5-silolene)-co-(ethynylene)]s (R=Et, i-Pr, n-Hex, 2a-c) as blackish solids, respectively. All structures of the prepared silole-ethynyl copolymers were characterized by ¹H NMR, 13C NMR, FT-IR, and UV-vis spectral data, and thermal stabilities were measured using TGA. The synthesized silole copolymers were consistent with the structures proposed in the reaction scheme 1. The band gaps of 2a-c were measured from UV-vis spectral data, resulting in 1.73, 1.74, and 1.73 eV, and compared with calculated values of 1.62, 1.80, and 1.66 for the trimeric forms of the model compounds, respectively; we applied the Density Functional Theory using Gaussian 09W and B3LYP/6-31G basis. The maximum absorption wavelengths of 2a-c were measured between 555 and 575 nm, indicating that the polymers might be conjugated through the copolymer main chain. The prepared silole-ethynyl copolymers 2a-c were very stable, with a weight loss of less than 2% up to 200℃ in nitrogen atmosphere.