The contactless slipring based on wireless power transfer (WPT) technology is an important power supply interface for rotating equipment. Ferrite magnetic strips are generally used as magnetic shielding to suppress the leakage magnetic field generated on the slip ring, but which will result in problems such as wear and excessive weight. This paper introduced a resonant reactive shielding structure for the contactless slipring in rotating equipment. A resonant power supply system with series-series (SS) topology is designed, and a structure with optimal shielding effect for the target surface is proposed based on the resonant coil shielding theory. Firstly, the functional relationship between the magnetic flux of target surface and equivalent inductance is established based on the SS topology. It is found that the optimal inductance is related to load and shielded coil parameters. Then the simulation model is established by COMSOL to explore the optimal inductance value of the shielded coil. Finally, the proposed shielding is proved to reduce magnetic flux on the target surface by 76%.