Abstract: Magnetron sputtering, as an efficient and controllable physical vapor deposition technique, is widely applied in large-area thin film coating. This study employs a Particle-in-Cell/Monte Carlo Collision model to simulate the direct current planar magnetron discharge, combined with a Monte Carlo-based sputtering model to simulate target sputtering and the transport of sputtered atoms. Under a working pressure of 5 mTorr and an applied voltage of −300 V, the effects of magnetic field distribution (by varying the dimensions of the inner magnet in the magnetron target), ion-induced secondary electron emission coefficient, and resistance on plasma characteristics and surface sputtering in magnetron discharge are systematically investigated. The results indicate that the confinement of electrons by orthogonal electromagnetic fields confines the plasma predominantly to regions where the magnetic field is parallel to the target surface. Compared to adjusting the width of the inner magnet, modifying its height exerts a more pronounced influence on the magnetic field distribution. Reducing the height of the inner magnet significantly shifts the position of the magnetic field parallel to the target surface, transforming the plasma density distribution from oblique to perpendicular to the target surface, thereby enhancing the vertical incidence of ions onto the target. Additionally, sputtered atoms exhibit nearly isotropic motion characteristics. As the substrate-to-target distance increases, the atomic flux reaching the substrate gradually decreases, but the uniformity improves significantly.