The invention relates to a production method and a device for making salt by concentrating brine by using terrestrial heat. The production method comprises the following steps: feeding high-temperature brine into a main flash tank for flash cooling, subsequently dividing a material liquid into two paths, feeding one path of the material liquid into a multi-effect flash system for flash, feeding a mother liquid after end-effect flash into a settler for settling and separating solid salt, feeding an overflowing clear liquid into a low-temperature brine storage tank, wherein the end-effect flash material liquid temperature is the conveying temperature; feeding the other way of the material liquid into a multi-effect evaporation system, performing flash cooling and heat evaporation on the material liquid inside the tank till the temperature of the material liquid inside an end-effect evaporation tank is controlled to be the conveying temperature, respectively discharging the evaporated and crystallized salt slurry and the separated mother liquid, performing centrifugal separation on the salt slurry, and drying, thereby obtaining refined salt, wherein the secondary flash steam from the main flash tank is used as the heat source for heating an I-effect evaporation tank, and secondary steam obtained from an I-effect flash tank and the I-effect evaporation tank is used as the heat source for heating an II-effect evaporation tank. By adopting the production method and the device, not only is the problem that high-temperature brine cannot be conveyed for a long distance solved, but also the solid salt can be produced by using terrestrial heat of the high-temperature brine is sufficiently utilized, and thus the economic benefits of companies are increased.