To improve the corrosionresistance of traditional steel DC ground electrode, pure NiFe₂O₄ powders were synthesized by solid state reaction. Via the powder granulation by grain aggregation and crushing, the NiFe₂O₄ ferrite coatings were prepared on the steel substrate through plasma spraying technology. The phase and microstructure of the coating were investigated by fileld emission scanning electron (FESEM), metallographic microscopy and Xray diffraction (XRD), while the physical and electrical properties of the coating were measured by bonding strength, resistivity and DC electrolysis tests. The results showed that the mean adhesion strength of the coating was 21.8 MPa, and the average resistivity of NiFe₂O₄ coating was about 3.60×10^-2 Ω·cm, as well as the electrolysis corrosion rate was about 1.86 g/(A·a), which could satisfy the performance needs of DC ground electrode materials. This study also indicates the feasibility of corrosionresistant ferrite coating preparation using plasma spraying technology.