A device for recovering magnetic particles trapped on a magnetic plug, which includes a supporting end and a magnetized element for retaining the magnetic particles in a liquid resulting from the wear of parts with which the liquid has been in contact, the recovery device including a magnetization device and an enclosure having an opening, the enclosure to receive the magnetic plug via the opening such that the magnetized element is located inside the enclosure and the supporting end is located outside the enclosure. The opening is sized such that the supporting end blocks the opening. The device also includes an injection nozzle to inject a gaseous fluid inside the enclosure, the nozzle being oriented such that the flow of gaseous fluid expels the magnetic particles retained on the magnetized element toward the bottom of the enclosure. The magnetization device traps the particles urged toward the bottom of the enclosure.