Thermal conductivity values of gaseous hydrogen chloride, hydrogen bromide, boron trichloride, and boron trifluoride have been experimentally determined at one atmospheric pressure and in the temperature range from 55 to 380 degrees C using a differential hot-wire method. Thermal conductivity values of argon were also measured for the purpose of checking the accuracy of the instrumentation. The experimental values are compared with the available literature results. The reproducibility of the results was within 4% over the temperature range.