A signal processing system includes: an interference source; and a band-stop filter. A first terminal of the band-stop filter is electrically connected to the interference source, a second terminal of the band-stop filter is grounded, and the band-stop filter is configured to filter a baseband signal output by the interference source. The interference source includes a first main board; or the interference source includes a target module and a metal frame used for fastening the target module, and the target module is a display module or a camera module.