In an attempt to construct a new kind of rodlike polyelectrolyte, poly[sodium 2,5-bis(4'-sulfophenyl)styrene] (PSBSS) was prepared from its precursor, poly[2,5-bis(4'-neopentylsulfophenyl)styrene] (PBNSS), which was polymerized by atom transfer radical polymerization. Small-angle X-ray scattering (SAXS) results demonstrate that PBNSS exhibits a hexagonal columnar phase and PSBSS exhibits a smectic A phase in bulk. The conformation of PSBSS in the aqueous solution is cylindrical, and the length and the diameter of the cylinder are ca. 25 nm and ca. 2.4 nm, respectively. The persistence length (l(p)) of the PSBSS chain in the aqueous solution is 11.50 +/- 0.09 nm calculated by fitting the SAXS profile with the modified wormlike chain model. The conformation, the maximum length, and the lp of the chain are only weakly dependent on the concentration of the added salt. These results indicate that we have successfully obtained a new kind of polyelectrolyte with a highly rigid chain, a high charge density, and a narrow molecular weight distribution, which can serve as a new model macromolecule in studying rodlike polyelectrolytes.