Abstract: To address the technical challenge of non−magnetic mineral inclusion in existing magnetic separation equipment, this study proposes a mineral separation method based on the density difference of magnetic induction lines. By deviating the magnetic force on minerals from the direction of the magnetic system, this method effectively avoids the inclusion of non−magnetic particles. A corresponding symmetric closed magnetic system was designed, and its magnetic field distribution characteristics were verified using magnetic field numerical simulation software. To accurately predict the separation performance of the magnetic system for magnetic minerals, this study designed and optimized key structural parameters of the symmetric closed magnetic system, such as the dip angle and spacing of magnetic pole plates. Numerical simulation and experimental results indicate that the regional magnetic field intensity reaches its maximum when the dip angle of the magnetic pole plates is in the range of 20°–30°, and the smaller the spacing between the magnetic pole plates, the higher the regional magnetic field intensity. The simulated force values of magnetic particles in the magnetic field are in good agreement with the experimental measurement values, confirming the accuracy of the established numerical model. This separation method can fundamentally reduce non−magnetic mineral inclusion and provide a new technical approach for the high−quality recovery of magnetic minerals.