As a common phenomenon, friction noise and vibration of the brake not only affect vehicle braking performance and riding comfort but also cause urban noise pollution. The studies of magnetic field tribology show that magnetic field has an important influence on tribological behavior, but research on the effect of the magnetic field on friction noise and vibration characteristics of the brake is still being carried out. Friction noise and vibration tests of the brake under a DC magnetic field were conducted on a disk brake friction noise-vibration test bench. Harmonic wavelet packet, scanning electron microscope (SEM), and energy dispersive spectroscopy (EDS) were used to reveal the influence mechanisms. Results showed that compared to the self-made collaborative brake, the commercial brake has worse friction noise and vibration phenomena. The DC magnetic field can significantly suppress the friction noise and vibration of the brake. The DC magnetic field’s main mechanism is that it attracts debris particles and promotes oxidation reactions, leading to a significant increase in oxygen, iron, and nickel elements on the wear surface, improving the morphology of the wear surface, and reducing friction noise and vibration. The research results are beneficial to enriching the research connotation of magnetic field tribology and providing a theoretical reference for exploring and developing the treatment of friction noise based on magnetic fields.