Abstract: In order to clarify the effect of the atmosphericpressure on the heat and moisture transfer within hygroscopic fabrics,based on the improved sorption rate equation and the Darcy's law, ananalytical model is proposed. From the fit between thetheoretically calculated temperature changes and those measured fromexperiments, it is shown that the models can predict the simultaneousheat transfer that is coupled in the moisture-diffusion process duringhumidity transients. Furthermore, the temperature and moistureconcentration distribution in the inter-fiber void space at differentatmospheric pressure conditions are numerically computed and compared.It shows that at the low atmospheric pressure, thetemperature peak and the density of vapor are higher than those at thehigh atmospheric pressure.