Geothermal water in high-temperature and high-pressure environments slowly infiltrates and migrates through fissured rocks to achieve a new thermal and dynamical balance conducive to dissolution, resulting in wall rock alteration. In the surrounding rocks, new substances are dissolved in the water, which enables the chemical indicators of geothermal water to be different from those of the surrounding environmental water, as shown by the fact that the values of F, SiO₂, and pH are much larger in geothermal water than in environmental water. We used the three indicators mentioned above as tracer elements to search for geothermal water in the Paoshouying hot spring area, in Dandong City. The results show that this method can explicitly define the boundaries of geothermal regions, narrow down the investigation targets, and reduce the original workload and capital investment.