Poly(diaryl)stannanes were prepared by the dehydropolymerization of secondary hydrostannanes Ar2SnH2 with dimethylzirconocene catalyst. At room temperature, H(Ar2Sn)(n)H polystannanes (Ar = p-Bu-t-C6H4, p-(HeX)-He-n-C6H4, o-Et-C6H4, o-Et-p-(BuO)-Bu-n-C6H3, p-(BuO)-Bu-n-C6H4, p-(Me3Si)(2)N-C6H4) exhibit lambda(max) values attributed to sigma --> sigma* transitions in the range 430-506 nm. These values vary according to the polymer molecular weights and are independent of temperature between -20 and 90 degrees C. A sample of poly[bis(o-ethyl-p-nbutoxylphenyl)]stannane exhibits a strong UV-vis absorption at 506 nm (tailing to ca. 550 nm), which corresponds to the smallest band gap yet observed for a group 14, sigma-conjugated polymer. The H(Ar2Sn)(n)H polystannanes undergo photodecomposition in solution to give a mixture of the cyclohexamer and the cyclo-pentamer. Thermal gravimetric analyses for the polymers suggest that H(Ar-2-Sn)(n)H polystannanes are thermally stable and have onset temperatures for thermal decomposition in the range 180-320 degrees C, under both nitrogen and air. The H(Ar2Sn)(n)H polystannanes undergo clean thermal decompositions to elemental tin (under nitrogen) or tin oxide (under oxygen or air), as shown by bulk pyrolysis.