Crystallization fouling of a heat exchanger surface under an alternating magnetic field was studied by using a self-designed annular channel electromagnetic anti-fouling experiment platform to obtain experimental data including conductivity, induced current and fouling resistance in various magnetic induction intensities. The magnetic induction intensity of 300 Gs exhibited the best fouling inhibition effect, and the fouling inhibition rate was 78.89%. The induced current (first proposed in the research) was related to the change of magnetic induction intensity and salt concentration, which could directly reflect the characteristics of fouling resistance and alternating magnetic field. Based on the strong correlation between conductivity, induced current and fouling resistance, support vector regression (SVR) optimized by improved grey wolf algorithm (IGWO) was proposed to predict fouling resistance with conductivity and induced current as input variables, fouling resistance as output variable. Keeping other experimental conditions constant, the fouling resistance on the heat exchanger surface under the same and different magnetic induction intensities was predicted. Prediction results indicated that, the mean absolute percentage error was 3.24% for the former, 7.88% (300 Gs) and 4.04% (100 Gs) for the latter. IGWO–SVR had the highest prediction accuracy and the strongest generalization capability compared with support vector regression (SVR) and SVR optimized by genetic algorithm (GA–SVR), which demonstrated that IGWO–SVR was highly adaptable to predict fouling resistance in various situations.