The equilibrium moisture contents (EMC) of three black teas and three green teas were determined by the gravimetric static method at 35 ℃ over a range of water activity from 0.06 to 0.90. The sorption isotherms have an S-shape profile typical for many food materials. A hysteresis effect was observed. The experimental data were analyzed by SPSS software for the single factor analysis of variance, the analysis results show that different kinds of tea have the similar adsorption and desorption equilibrium moisture content.