Abstract: Induction machines(IMs) are widely utilized in industry, agriculture, and daily life. They operate in severe environments and require high reliability. Load oscillation and rotor unbalance may lead to lateral vibration on the shafts. To improve the reliability of the shaft systems, a lateral vibration diagnosis method based on electromagnetic forces is proposed. The finite element analysis(FEA) for IMs takes a long time. The analytical model of radial electromagnetic forces on temporal and spatial dimensions is built to analyze lateral vibration’s effect on IMs efficiently, which retains the amplitude, frequency, order, and phase. Finally, the models under normal and lateral vibration are verified by FEA and experiments.