Uncatalyzed synthesis of a new ionic conjugated polymer, poly(3-ethynyl-N-pentylpyridinium iodide) [P3EPPI] was performed by the activated polymerization of 3-ethynylpyridine using 1-iodopentane. The polymerization proceeded in homogeneous manner to provide amoderate yield of polymer. The polymer structure was characterized by such instrumental methods as NMR (H-1- and C-13-), IR, and UV-visible spectroscopies to have a conjugated polymer backbone system having N-pentyl-3-pyridinium iodide as substituents. The photoluminescence maximum peak of P3EPPI was located at 534 nm, which corresponds to the photon energy of 2.32 eV. The cyclovoltamograms of polymer exhibited the electrochemically stable window at the -1.53 similar to 1.50 V region. The kinetics of the redox process of P3EPPI was found to be mainly controlled by the reactant diffusion process from the experiment of the oxidation current density of polymer versus the scan rate.