Ammonia is one of typical index substances of environmental odor. This study describes a rapid and simpleadsorption tube type detector to be able to measure the level of strict emission standards with quantitative concentration of gaseous ammonia as the regulations are enhanced. a gas detector tube can be measured the ammonia gas concentration of 0.23 ppm, 0.5 ppm, 1 ppm, 1.5 ppm and 2 ppm through the relation between the Sampling rate Kog (=DA/L) and the discoloration reaction rate by physico-chemical analysis. Also this study can be predicted the relation between the sampling volume and the sampling time. and it can be designed to measuring the range of various concentrations. In this case study, an optimum design was found with an sampling rate, 42 ml/min and with a tube diameter, 3.0 mm. Adsorption and diffusion rate was evaluated by Fick\'s law. Keywords : Odor, Ammonia, Gas detector, Physicochemical adsorption