The invention provides a mechanical vapor recompression (MVR) type desiccant air-conditioning system, which is characterized by comprising a desiccant air-conditioning system and an MVR type solution regeneration device for regenerating a desiccant solution in the desiccant air-conditioning system. The invention discloses an MVR concentration technology and desiccant air-conditioning system combined air treatment device, which can concentrate and regenerate the desiccant solution by a vapor compressor, an evaporative condenser, a vacuum pump and the like to realize high-efficiency, energy-saving and economic recycling of the desiccant solution. Compared with the traditional system, the novel desiccant air-conditioning system has the advantages that the system COP, the dehumidifying effect and the operation stability are further improved and the advantages are significant.