Insertion of thiophene-2,5-diyl, or 1,4-phenylene into palladium poly-ynes by the polycondensation of dihalide complexes PdCl2(PR3)(2) (R = Ph o gamma n-butyl) with a di-yne monomer (obtained from the reaction of equimolar quantities of p-diethynylbenzene with 2,5-diiodothiophene or 1,4-diiodobenzene) affords a series of palladium poly-ynes 1-6. The polymers/oligomers, soluble in common organic solvents, exhibit strong fluorescence at the excitation of UV-visible light at room temperature. The emission intensity of the polymers/oligomers with thiophene-2,5-diyl is 3-17 times stronger than that of the analogous polymers without thiophene-2,5-diyl. Polymers with phenyl substituted phosphine ligands emit stronger emission than those only with n-butyl phosphine ligands. The effects of molecular weight, Ligands, solvents, and concentration on the fluorescence properties are also investigated.