In the newly developed geothermal well heating system， it is necessary to obtain more accurate reinjection data through multiple well reinjection experiments， so as to select the best reinjection well. After the geothermal well has been used for some time， the injection well and the production well are reversed. The traditional placement of the reinjection device is more like part of a building project， thus， without proper consideration of drilling operation， geothermal well drilling technology structure， early reinjection test verification， geothermal well maintenance and other factors. There are also some problems with the fixed reinjection device such as large footing area， high cost of investment， complex installation and maintenance. As a result， a mobile geothermal tail water reinjection device is designed and manufactured. This device is featured of simple structure， movement as one piece， rapid installation and transfer as well as multi-level filtration and auxiliary pressurized reinjection.