The adsorption isotherms of dried products of Benincasa hispida at six temperatures (1 0 ℃,20 ℃, 30 ℃,40 ℃,50 ℃ and 60 ℃)over a range of water activities from 0.1 09 to 0.982 were determined based on the adsorption theory.The experimental data of dried products of Benincasa hispida were fitted by seven models.The optimal model used to describe the adsorption isotherms of dried products of Benincasa hispida was determined by comparing the coefficient of determination (R2 ),root mean square error (RMSE)and the residual sum of squares (RSS).The net isosteric heat was determined from adsorption isotherms data of dried products of Benincasa hispida at different temperatures.The results showed that the adsorption isotherms of dried products of Benincasa hispida exhibited type Ⅲ sigmoid shape.At the same water activity,as the tem-perature increased with the decrease of the equilibrium moisture content.The Peleg model was found to be the best for describing the adsorption isotherms of the dried products of Benincasa hispida.The net isosteric heat of adsorption decreased with the increase of equilibrium moisture constant,and approached to zero at high mois-ture content (about 50%).%运用吸附原理，在水分活度为0．109～0．982条件下，研究冬瓜干制品分别在10℃，20℃，30℃，40℃，50℃和60℃时的水分吸附等温线；采用7种模型对实验数据进行拟合，通过对模型的决定系数（R2）、均方根误差（RMSE）和残差平方和（RSS）进行比较，确定描述冬瓜干制品吸附等温线的最优模型；通过不同温度下冬瓜干制品吸附等温线数据，确定净等量吸附热．研究结果表明：冬瓜干制品的水分吸附呈Ⅲ型等温线，且在相同的水分活度时，平衡含水率随着温度的升高而下降；Peleg模型为描述冬瓜干制品吸附等温线的最优模型；冬瓜干制品的净等量吸附热随着平衡含水率的增加而降低，在较高含水率（50％左右）时趋近于0．
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