The moisture sorption isotherms oftobacco stem and rice huskwere measured by using thegravimetric method at 30 oC within a range from 50%to 90%relative humidity.The exponential growth was found for moisture content of tobacco stem at 90%humidity,while equilibrium moisture content(EMC)of rice husk was reached after 12 h.Equilibrium moisture content of tobacco stem and rice huskranged from 10.51%to 45.29%and 7.62%to 19.24%respectively.EMCof tobacco stem was much higher than that of rice husk at the same humidity,and higher humidity led to a higher EMC.