The invention relates to a contact life test device. The contact life test device comprises a slotting machine, the ram of the slotting machine is detachably connected with a plugging piece used for carrying out a plugging test on a tested contact. The workbench of the slotting machine is detachably connected with a contact positioning tool used for positioning the tested contact. The contact positioning tool comprises a threaded connection part used for being matched with the internal thread of the tested contact and a basic part used for being matched with the clamping tool of the slotting machine in a clamping mode, and the plugging piece is provided with an outer circumferential face used for being matched with the inner circumferential face of a protruding structure in the upper end of the tested contact. Thus, the existing slotting machine can be used for testing the mechanical service life of the contact, so that the utilization rate of the slotting machine is improved; the contact positioning tool is clamped by the clamping tool on the workbench of the slotting machine, plugging and unplugging of the plugging piece in the contact are achieved through up-down reciprocating motion of the ram, so that the service life of the contact is tested; and moreover, the existing slotting machine is used for testing, the efficiency of contact service life detection is high, and thecost is low.