The invention relates to the technical field of auxiliary devices for tablet personal computer production and detection, in particular to a key life test device for a tablet personal computer. The placement stability of the tablet personal computer on a test bed can be improved; the tablet personal computer can be fixed, and the use boundedness can be reduced; furthermore, a user does not need totest a start-up key of the tablet personal computer, so the labor intensity is relieved; and the test effect and the practicability are improved. The key life test device comprises the test bed, a rear side plate, a sliding plate, two groups of threaded rods, two groups of rollers, two groups of locking nuts, an upper left locking plate, a lower left locking plate, an upper right locking plate, alower right locking plate, two groups of left locking bolts, two groups of right locking bolts, an upper locking belt, a lower locking belt, a left screw rod, a right screw rod, an upper left fastening nut, a lower left fastening nut, an upper right fastening nut, a lower right fastening nut, an adjustment plate, four groups of supporting rods, a placement plate, a servo motor, a cam, a pulley, atest rod, four groups of reset springs and a limiting plate.