Energization of transformer both unload and removal of fault is accompanied with an inrush current, the value of which depends on the angle of the applied voltage, residual flux of the core, the impedance of system and so on. A strategy of eliminating the single-phase transformer inrush current is proposed, which refers to set the transformer residual flux to a known value which is equal to the flux when energization by a pre-magnetizing device, while decreases the inrush current. By theoretical analysis, the relationship between size of capacitor and the voltage, the degree of magnetization of the core and the corresponding phase are determined. Finally, in case of a single-phase transformer, the proposed strategy is verified by Simulink simulation.