Superconducting electrodynamic suspension (EDS) maglev technology has strong potential for ultra-high-speed transportation, with advantages such as self-stability and a large suspension gap. The magneto-electric force relationship between the onboard superconducting magnet and figure-eight null-flux coils is the key to improving system performance. This article shows a novel study on the impact of the shape of null-flux coils on the superconducting EDS maglev system, which has not been systematically studied before. A 3D model of the suspension system of EDS maglev was built using the finite element method (FEM) to study the impact of the null-flux coils’ shape. The electromagnetic forces generated by the system were calculated and compared with those in the literature to validate the model. The results showed that rectangular and circular coils displayed different influences on the components of the electromagnetic force. New results and analysis from the article show that the null-flux coil shape is a promising option for system performance optimization and can provide a theoretical basis for future improvements to the high-speed EDS maglev system.