The invention provides a device for detecting an end position of a mobile electric igniter. The device comprises an isolation sleeve (12) and a movable bar (17) which is sleeved with the isolation sleeve (12). The axis of the movable bar (17) is arranged in the horizontal direction, the right end of the isolation sleeve (12) is sealed, and an elastic part capable of pushing the movable bar (17) to move leftwards is arranged between the movable bar (17) and the isolation sleeve (12). A driven part (9) capable of moving leftwards along with the movable bar (17) is arranged outside the isolation sleeve (12). The device for detecting the end position of the mobile electric igniter further comprises a measuring element (6) for detecting the position of the driven part (9). By means of the device for detecting the end position of the mobile electric igniter, it is detected automatically that the bottom end of the igniter passes over a wellhead valve, reliability and work efficiency of field operation are improved, and the risk of accidents is lowered.