The energy consumption in the field of rail transit is high, which is not only an important source of carbon emissions, but also a key area for promoting the development of green energy and achieving the dual carbon strategy goals. In order to achieve the goals of “carbon peak and carbon neutrality”, China’s rail transit is developing towards the trend of energy conservation and low-carbon. Energy storage technology can absorb regenerative braking energy on a large scale and improve the energy utilization efficiency of trains, which is an important means to achieve energy conservation and emission reduction in rail transit. This article introduces the high-capacity superconducting magnetic levitation (maglev) flywheel energy storage system used in the field of rail transit, and studies its electromagnetic bearings, superconducting bearings, and rotor dynamics analysis. It also explores its application prospects in the field of rail transit. With the continuous advancement of technology, superconducting maglev flywheel energy storage technology is expected to play a greater role in the field of rail transit, providing strong technical support for achieving green transportation and sustainable development goals.