Grounding network is an important guarantee for safe operation of power system. In this paper, a study is conducted through field test on the relationship between applied current and corrosion potential of galvanized and non galvanized Q235 and Q345 steel in different soil environments and on the relationship between the burial time and corrosion rate, and the corrosive properties of the Q235 and Q345 steel in different soil environments are obtained. The field test result shows that along with the increase of the applied current, the corrosion potential of 4 different steel decreases first before going up, with the corrosion potential of the Q235 carbon steel being the lowest; The non galvanized Q235 steel has the lowest fitting degree between the tested corrosion rate and the corrosion rate model while the non galvanized Q345 steel has the highest.