The experimental studies of fin-tube type internally-cooled dehumidifiers are still limited until now. In the present paper, the performance of a cross-flow internally-cooled dehumidifier is studied by both of experiment and simulation. The dehumidifier is made up of fin-tube heat exchangers with high corrosion resistance. Compared with the dehumidifier of the literature, it is found that the dehumidifier of this work performs well in terms of the dehumidification efficiency. Meanwhile, the heat transfer coefficient is correlated on the basis of the experimental data. By applying the correlated coefficient, the theoretical model can predicate the performance of the dehumidifier with an acceptable accuracy. Then the validated model is employed to give suggestions for optimizing the geometry design and operating conditions of the dehumidifier. Through calculation, it is discovered that the best length of the air flow direction for the present dehumidifier is about 0.3 m. In addition, the ratio of solution to air flow rate can be decided by the simulation as well. (C) 2014 Elsevier Ltd. All rights reserved.