The invention relates to a same-tooth positioning device with single gear tooth continuous induction quenching, which comprises a stand, a sensor, a front positioning guide block, an insulation board I, an insulation board II, a rear positioning guide block, a front fixing block and a rear fixing block, wherein the stand is fixed on a machine tool bracket; the front fixing block and the rear fixing block are fixed on the stand through a screw II; the stand is provided with an opening slot; the front fixing block, the front positioning guide block, the insulation board I, the sensor, the insulation board II, the rear positioning guide block and a rear fixing block are sequentially arranged in the opening slot from left to right; the sensor is fixed on the insulation board I and the insulation board II through an adjusting screw II and an adjusting screw III which can adjust a gap between an adjustable sensor and a gear outline; the sensor, the insulation board I and the insulation board II are assembled into a whole; and the front fixing block, the front positioning guide block, the insulation board I, the sensor, the insulation board II, the rear positioning guide block and the rear fixing block are sequentially fastened by a screw I and a fixing screw from left to right. The same-tooth positioning device with single gear tooth continuous induction quenching has simple operation and high production efficiency.