Abstract: In order to study the absorption of strips and the migration rate of moisture in strips during proce-ssing,B₂F strips were studied dynamically under a temperature range of 60-80℃ and relative humidity range of 60%-90% by an online device on the presumptions that:1) The test piece is homogeneous and of even initial temperature;2) Coupling effect and temperature difference in the test piece are negligible during heat and mass transfer process;3) The distortion and expansion effects of the test tobacco during humidifying are ignored,and the thickness of the test tobacco is represented by its mean,3×10^-4 m;4) The humidifying process follows Fick's second law,the dynamic model of humidifying process,which describes the effects of temperature and humidity,was established;the model was modified and verified.The results showed that:1) At the same temperature,effective diffusion coefficient D_e decreased with the increase of relative humidity;while D_e increased with the rise of temperature at the same relative humidity;2) The modified model could describe the humidifying process of B₂F strips in the environment of higher temperature and relative humidity,the verified experimental data well agreed with the calculated values by the model,and correlation coefficient R² was 0.95.