Abstract: In order to solve the scaling problem during field production, analyze the scaling phenomena and scale component during off shore field production, study the characteristics of magnetic treating. After the experimental research, have selected optimally the optimal magnetic parameters of ferromagnetic treating, and based on which designed and manufactured the ferromagnetic scale inhibition device suitable to off shore field. The ferromagnetic scale inhibition technique has been used in an off shore field. The production comparison between after and before the ferromagnetic scale inhibition device is used indicates:the ferromagnetic scale inhibition technique has achieved obvious effect. This paper also discusses the mechanism of scaling phenomena and ferromagnetic scale inhibition.