In this paper, different Mn content doped potassium sodium niobate (KNMN) coatings were prepared by plasma spraying technology, and the effects of different Mn content doping on the microstructure and electrical properties of the coatings were investigated. The results showed that the mechanical and electrical properties of the coatings showed a trend of increasing and then decreasing with the increase of Mn doping content, and the best mechanical and electrical properties of the coatings were obtained when the Mn doping content was 2 mol%. [ABSTRACT FROM AUTHOR]