In this paper, the design and thermodynamical analysis of a liquid desiccant dehumidication system, which can be used instead of mechanical dehumdification systems, was done. The main parts of the designed and produced system are absorber, regenerator and heat exchangers. In proposed open liquid desiccant system, packing material was prepared from polycarbonate plates, which haven't be used before as packing material. The channel angle of the prepared polycarbonate packing material to be 30°. LiBr-Water (Lithium bromidewater) solution was used in the system as desiccant and the performance of the system was investigated in terms of dehumidification efficiency, enthalpy efficiency and sensible heat ratio parameters. As a result of the analysis, dehumidification efficiency of the liquid desiccant system was found 15%.