The specific conductivity of the pure binary NaCl-AlCl//3 molten salt system was measured in the temperature range 175-400 degree C and with the mole fraction of AlCl//3, X//A//l//C//l//3, ranging from 0. 497 to 0. 600. Sulfur, aluminum metal, and sodium chloride were dissolved in the NaCl-AlCl//3 solvents at ca. 250 degree C, forming polymeric NaAlSCl//2. The specific conductivity of these melts was measured in the range 0 less than X//A//l//2//S//3 less than 0. 08. All conductivity data are given as a polynomial function of temperature and composition. This work is pertinent to molten salt batteries.