The values of various physical properties such as specific heat, thermal conductivity of humid air are necessary for designing various food processing. The values vary with the temperature and humidity, and must be obtained from the humidity chart and the various empirical equations. We must select a useful equation from the humidity chart and reported equations. In this study, we sutudied the convenient equations of phsical properties regarding humidity chart for personal computer. The equations obtained will be useful to rough estimate of various physical propertied of humid air from the dry- and wet-bulb temperature data etc.