In the present study, the ionic effect of salt addition to a lyotropic liquid crystal (LLC) system was investigated. NH4Br salt was added to TTAB + water + decanol ternary system and the structural changes in lyotropic phases were characterized. First, phase transitions were illustrated by polarized microscope and secondary, small-angle x-ray scattering was used as an analytical method to determine the nano-structured mesophases of the newly prepared liquid crystal samples. The expected fibrous structures were characterized by the form factor of polydisperse oblate ellipsoids. The self-assembled networks related with these ellipsoids were also explained with hexagonal, distorted hexagonal, and lamellar formations.