Abstract: In order to study the corrosion and scaling behavior of 20 steel in geothermal water environment in Guanzhong area, the water quality of geothermal water in a community in Guanzhong area was analyzed. The scaling tendency of geothermal water was analyzed by Ryznar index method. The corrosion behavior of 20 steel in geothermal water environment at 50 ℃, 70 ℃ and 90 ℃ was studied by corrosion electrochemical method and weight loss method, and the surface of the coupon was characterized. The results show that the geothermal water in a community in Guanzhong area is weakly alkaline,the content of scaling cations is low, the scaling tendency of geothermal water is not serious, and the scaling trend increases with the increase of temperature. The corrosion form of 20 steel in geothermal water is uniform corrosion. With the increase of temperature, the corrosion rate and the maximum corrosion depth increases gradually. The corrosion resistance of 20 steel in geothermal water environment is better. The main elements in the corrosion product layers are C, O and Fe, and the main factor causing corrosion is dissolved oxygen.