An electronic device comprises a main body and a stylus. The main body comprises a front cover, a conducting sheet, a conducting core, and a monitoring module. The front cover defines an elongated pocket. The conducting sheet is disposed in the elongated pocket. The conducting core is disposed in one end of the elongated pocket. The monitoring module electrically connected with the conducting sheet and the conducting core. The stylus received in the elongated pocket comprises an outer section, a conducting layer, and an inner section. The outer section comprises a tip and a stripped slot. The conducting layer is mounted on the stripped slot. The conducting layer is electrically connected with the tip. The inner section comprises a protrusion, the inner section is sleeved in the outer section, and the protrusion protrudes out of the second tube and slidably contacts with the conducts layer and the conducting sheet.