The invention relates to a method and a device for producing calcium chloride solution through concentration, which belongs to the technical field of calcium chloride solution concentration. The method comprises the following steps: firstly, two sections of coordination methods that a mechanical steam recompression evaporator and a triple effect evaporator with a steam jet pump are combined are adopted for concentrating the calcium chloride solution; secondly, the method for the mechanical vapor recompression evaporator adopted at the first section comprises the following steps: the raw materials enter into the first section of the evaporator (3) to be heated and vaporized, the generated secondary steam carried with a small part of calcium chloride solution enters into a separator (4) for separation, then the separated secondary steam enters into a compressor (5) for compression, the compressed secondary steam is introduced into a shell side of the first section of the evaporator (3) after temperature rise and pressure increase, then the calcium chloride solution in the tube side is heated, and after the separated calcium chloride solution is mixed with unevaporated calcium chloride solution, the mixed solution is delivered to a second section of process pump from a first section of process pump (6). By adopting the method and the device, both the energy resources and the investment are saved, and the running cost is reduced.